ChemGlobe: Mercury
   Electronic, thermal, and steric data along with an isotope table.
   http://partisans.spurious.biz/~pkremer/projects/chemglobe/ptoe/_/80.html

ChemicalElements.com: Mercury
   Basic information, atomic structure, and isotopes.
   http://www.chemicalelements.com/elements/hg.html

EnvironmentalChemistry.com: Mercury : Nuclides
   Extensive information on the nuclides of mercury, including potential parent nuclides.
   http://environmentalchemistry.com/yogi/periodic/Hg-pg2.html

It's Elemental: Mercury
   Basic physical and historical information.
   http://education.jlab.org/itselemental/ele080.html

LANL: Mercury
   Basic information, history, and uses.
   http://periodic.lanl.gov/elements/80.html

Lenntech: Mercury
   Physical data, chemical properties, health and environmental effects.
   http://www.lenntech.com/Periodic-chart-elements/Hg-en.htm

Mercury
   A very brief description of Mercury, with a good diagram of its electron orbitals.
   http://www.pleasantridge.k12.ca.us/magnolia/elements/mercury/mercury1.html

Mercury and Methylmercury by IC-ICPMS
   Analysis of biological, pharmaceutical, and environmental samples for methylmercury and mercury.
   http://www.wcas.com/tech/methylhg.htm

Mercury in Space
   Answers the question of what happens to Mercury in space.
   http://www.newton.dep.anl.gov/askasci/phy99/phy99189.htm

Mercury in the Laboratory
   Practical considerations when working with mercury in the laboratory.
   http://www.ilpi.com/safety/mercury.html

Mercury, Get Mad Now, Not Later
   Gives a description of mercury, as well as its uses and environmental and health hazards associated with it.
   http://www.wlssd.duluth.mn.us/publications/mercury.htm

Radiochemistry of Mercury
   Full text of the monograph by Josef Roesmer (Westinghouse Astronuclear Laboratory, Pittsburgh, Pennsylvania). [PDF]
   http://lib-www.lanl.gov/cgi-bin/getfile?rc000030.pdf

USGS Minerals Information: Mercury
   Statistics and information on the worldwide supply, demand, and flow of the element (PDF format).
   http://minerals.usgs.gov/minerals/pubs/commodity/mercury/

Vermont Legislative Research Shop - Mercury Information
   Features basic information about Mercury, as well as its harmful effects and legislation concerning Mercury in some American States.
   http://www.uvm.edu/~vlrs/doc/mercury.htm

Visual Elements: Mercury
   Image, general and physical information, source, uses, key isotopes, and ionisation energies.
   http://www.chemsoc.org/viselements/pages/mercury.html

Why Worry About Mercury : Chemical Properties
   Gives some chemical properties of mercury, as well as hazard precautions when dealing with mercury.
   http://pasture.ecn.purdue.edu/~mercury/src/why2.htm#properties

Why is Mercury liquid at room temperature?
   Explores the question of why Mercury is liquid at room temperature. It also provides some links to other sites regarding this chemistry quandary.
   http://www.zyra.org.uk/mercliq.htm

Wikipedia: Mercury
   Properties of the element, including its history, applications, and characteristics.
   http://en.wikipedia.org/wiki/Mercury_(element)