A Periodic Table of the Elements at Los Alamos National Laboratory
   [Very basic data, detailed write-ups] The Chemical Science and Technology division's Periodic Table describes the history, properties, resources, uses, isotopes, forms, costs, and other information for each element.
   http://periodic.lanl.gov/

ChemicalElements.com: Online Periodic Table
   [Basic data, limited write-ups] Provides information on the 109 named elements plus elements 110 - 112.
   http://www.chemicalelements.com

Chemicool Periodic Table
   [Detailed information on each element, no write-ups]
   http://www.chemicool.com/

Chemistry / Periodic table Quiz
   Millionaire type periodic table quiz. Has a link to other science quizzes.
   http://www.triv.net/html/Users1/u4237.htm

Chemistry.org Periodic Table from the American Chemistry Society
   [Comprehensive] Interactive periodic table which includes enthalpy of fusion, vaporisation and molar heat capacity. Diagrams of electronic configurations and data graphs.
   http://chemistry.org/portal/a/c/s/1/acsdisplay.html?DOC=sitetools%5Cperiodic_table.html

David's Whizzy Periodic Table
   Applet-based table with visualizations of the electron shell model, the nucleus, the visual emission spectrum, and energy levels of the electrons. Also has interesting facts about each element represented.
   http://www.colorado.edu/physics/2000/applets/a2.html

DreamWave Periodic Table of the Elements
   An interactive javascripted periodic table, which contains basic element properties.
   http://www.dreamwv.com/primer/page/s_pertab.html

Elemental - Is it time to revamp the periodic table?
   Article by Jon Lackman, on Slate magazine, about an alternative periodic table, shaped as a galaxy, designed by Oxford ecologist Philip Stewart. Includes a slide show and pictures.
   http://www.slate.com/id/2122919?nav=wp

Elements of life
   Educational/promotional flash presentation highlighting the roles of several chemical elements in a diverse range of end products.
   http://www.elements-of-life.org/

Elementymology and Elements Multidictionary
   Explains the origins of the names of the chemical elements and lists element names in scores of languages.
   http://www.vanderkrogt.net/elements/

Engineers Edge
   [Basic] Simple periodic table of elements.
   http://www.engineersedge.com/periodic_table_of_elements.htm

EnvironmentalChemistry.com: Periodic Table of Elements
   [Very comprehensive data, write-ups, extensive listing of nuclides] Data on elements includes scores of properties, element names in a dozen languages and almost all known nuclides. Environmental chemistry articles round out site.
   http://environmentalchemistry.com/yogi/periodic/

Exploring the Table of Isotopes
   [Nuclide data only, extensive listing of nuclides] Provides isotope data for almost all known nuclides. From Berkeley Laboratory.
   http://ie.lbl.gov/education/isotopes.htm

Extended Periodic Table
   [Very basic data] Predicted periodic table for undiscovered elements with atomic number greater than 118. Theoretical discussion and Orbital freeware available.
   http://www.apsidium.com/

Gordon England's Periodic Table of the Elements
   [Detailed data]
   http://www.gordonengland.co.uk/elements/index.htm

InfoFries - PDF Periodic Tables
   Provides various printable periodic tables in PDF format - from the simplest to the very detailed.
   http://infofries.freehostia.com/science/periodic_tables.php

Infoplease.com: Periodic Table
   An interactive periodic table with information about each element including the symbol, boiling point, melting point, discoverer and origin.
   http://www.infoplease.com/periodictable.php

Interactive Periodic Table
   Easily visualize relative differences between elements by dynamically coloring table (and generating graphs) based on elements attributes.
   http://www.touchspin.com/chem/

It's Elemental - The Periodic Table of Elements
   [Detailed data] Interactive periodic table. Including melting point, density, element history and crustal and oceanic abundance.
   http://education.jlab.org/itselemental/

Large color text-only printable periodic table
   [Basic data] All data including electron configuration on one page, available as PDF, PNG, and HTML.
   http://www.dayah.com/periodic/

Lenntech Periodic table
   Interactive periodic table. Containing physical data, chemical properties and health and environmental effects. Available in five languages.
   http://www.lenntech.com/periodic-chart.htm

Model Periodic Table - Model Science Software
   [Basic data] Interactive periodic table by Model Science Software. Available in English and Spanish, web based, Windows and Mac versions. Includes customizable quiz features.
   http://modelscience.com/PeriodicTable.html

NIST Ground Levels and Ionization Energies for the Neutral Atoms
   [Basic] Periodic table includes ground-state electron configuration, ground-state level, ionization energy, state and frequently used fundamental physical constants.
   http://physics.nist.gov/PhysRefData/IonEnergy/ionEnergy.html

On-line The Periodic Table of Elements
   [Basic data, requires JavaScript] Includes historical information about the elements in Italian, but the table itself is in English.
   http://www.themeter.net/elemen_e.htm

PTE Periodic Table of the Elements
   [Very basic data, includes writeups, Requires Javascript]
   http://pte.8k.com

Periodic Table
   An interactive clickable periodic table of the elements, which contains basic element properties and descriptions.
   http://the-periodic-table.org/

Periodic Table ADventure
   [No data] Includes the history of the periodic table and information on the structure of atoms and the periodic table.
   http://web.buddyproject.org/web017/web017/

Periodic Table of Data
   [Basic data] Interactive periodic table. Including uses and discovery.
   http://www.chemsoc.org/networks/learnnet/ptdata/welcome.htm

Periodic Table of Elements
   [Detailed] Includes general information about an element, atomic number and weight, shells and filling orbital, melting and boiling point, covalent and atomic radius, and lots of other parameters.
   http://atlas.chemistry.uoc.gr/ptoe/

Periodic Table of Parameters
   [Basic] This table lists and describes some well documented and validated parameter sets available for modeling each element by Molecular Mechanics and Quantum Mechanics molecular modeling methods.
   http://www.chamotlabs.com/Freebies/Table/parameters-table.html

Periodic Table of the Elements
   [Basic data] Simple click on periodic table. Includes electrical conductivity and ionization energies.
   http://www.crunchmachine.com/scieng.html

Periodic Table of the Elements - ChemGlobe
   [Detailed data, includes write-ups, basic nuclide data, printable version] Chemical elements database from ChemGlobe.
   http://partisans.spurious.biz/~pkremer/projects/chemglobe/ptoe/

Periodic table
   Printable Interactive periodic table of the elements, chemistry data tables and pictures of elements.
   http://profmokeur.ca/chemistry/

Printable Periodic Table
   [Very basic data] Minimalist table that provides symbols, atomic numbers, and atomic weight with four significant figures.
   http://www.swansontec.com/selement.htm

Printable periodic table
   Two up-to-date periodic tables in PDF format.
   http://www.profmokeur.ca/chemistry/printable_periodic_table.htm

Proton Don - Funbrain Periodic Table Game
   A fun way for youngsters to learn the periodic table. Includes learning by symbol or by name.
   http://www.funbrain.com/periodic/

Quiz Hub: Element Symbol Quiz
   [Basic data] Quiz that involves remembering symbols. Includes copy of periodic table with data.
   http://quizhub.com/quiz/f-elements.cfm

Science-Park's Periodic Table of the Elements
   [Detailed data] Interactive periodic table including boiling and melting point, discovery, thermal conductivity and density. Nice section where you can put the elements in order of their conductivity, melting point and other properties.
   http://www.science-park.info/periodic

Science: Periodic Table from tcaep.co.uk
   [Detailed data] Interactive periodic table. Includes electronegativity, density, conductivity and molar volumes.
   http://www.tcaep.co.uk/science/periodic/

Table of the Nuclides
   [Nuclide data only, very extensive listing of nuclides] Map of all known nuclides, with their atomic mass, radioactive decay modes and half-lives, and related information. Brookhaven National Laboratory.
   http://atom.kaeri.re.kr/

The 'Periodic Table' Table
   [Basic data] Based on a wooden 'periodic table' table. Contains photographs of over 200 element samples, with descriptions, experiments, and stories about many of them. Winner of the 2002 Ig Nobel prize in Chemistry.
   http://theodoregray.com/PeriodicTable

The Elements and Isotopes
   The Elements and Isotopes is a comprehensive application that will display information from the Periodic Table and the Table of the Isotopes.
   http://www.infini-t.com

The Extended Periodic Table Of The Elements
   [No elemental data] Alternate versions of the extended periodic table. Include information on symmetry and electronic configurations.
   http://jeries.rihani.com/

The Periodic Table
   Features an interactive table based on the IOUPAC 1985 standard.
   http://www.periodic-table.org.uk

The Periodic Table Challenge
   [No element data] An auto-scored blank periodic table. The user fills it in online and the score is returned automatically.
   http://www.ilpi.com/genchem/periodicquiz.html

VRML Periodic Table
   [Very basic date, requires VRML] Visual representations of the Bohr model of the atom in 3D.
   http://www.psinvention.com/periodic.htm

Visual Elements
   [Detailed data, write-ups, basic listing of nuclides] The Royal Society of Chemistry's (in the UK) contribution to chemistry on the web.
   http://www.chemsoc.org/viselements/pages/periodic_table.html

X-Ray Properties of the Elements
   [X-ray properties only] X-ray properties of most of the elements.
   http://www.csrri.iit.edu/periodic-table.html

YOGI's Periodic Table of the Elements
   [Basic data] Information includes nuclides.Interactive periodic table.
   http://www.uaf.edu/geology/reference/periodic/

eFunda: Periodic Table
   [Basic data] Interactive periodic table. Includes electrical resistivity, vaporization enthalpy and heat capacity.
   http://www.efunda.com/materials/elements/periodic_table.cfm