Mechanical Calculating Machines  
   Mechanical calculating machines from a collector's point of view, with articles and links to relevant sites.
   http://www.webcom.com/calc/

The Museum of HP Calculators  
   Information about every HP calculator made since 1968. Includes photo gallery, old advertisements, operating instructions, pricing information and discussion forum.
   http://www.hpmuseum.org

Museum of Pocket Calculating Devices  
   A gallery containing many varieties of pocket calculators, slide rules, and abacuses.
   http://www.calculators.de/

Calculator Technical Information  
   Technical information about many calculators, including chip pinouts and self-test sequences, and patent information.
   http://www.calcinfo.com/

The Old Calculators Web Museum  
   Virtual museum of vintage mechanical and electronic desktop calculators from the late 1950s through the late 1970s
   http://www.geocities.com/oldcalculators/

Museum of Soviet Calculators  
   Displays handheld and desktop calculators from the 1900s to the present, showing interesting features of each.
   http://www.taswegian.com/MOSCOW/soviet.html

Be Calc  
   Serge Devidts' collection of vintage electronic calculators and some other pieces of old technology.
   http://www.devidts.com/be-calc/

Programmable Calculators  
   A collection of programmable and non-programmable calculators and accessories, with articles and repair notes.
   http://www.rskey.org/

EEC - Early Electronic Calculator Technology Reference  
   A source of information about the technology used in the construction of early electronic calculators. Includes a reverse-engineering project.
   http://www.cs.ubc.ca/~hilpert/eec/

Soviet Calculators History  
   Article about the history of the development of Soviet calculators, the features and interesting characteristics of the most relevant models are described.
   http://www.dotpoint.com/xnumber/russian_calcs.htm

Gregory Escov's homepage  
   Some articles about Russian made calculators, including undocumented features and error conditions.
   http://members.tripod.com/GregEscov/

Datamath Calculator Museum  
   An overview of the calculators manufactured by Texas Instruments Inc. from the famous Datamath (1972) to the modern Graphics calculators, with history and articles.
   http://www.datamath.org

How to Collect LED Pocket Calculators  
   A guide by Larry Gilbert.
   http://www.ndirect.co.uk/~e.tedeschi/howto3.htm

Yahoo! Groups : oldcalcs  
   Bulletin board for collectors of old electronic calculators.
   http://groups.yahoo.com/group/oldcalcs/

Curta Calculating Machines  
   Links to useful sites about the Curta. Also documents the full disassembly of one, with pictures.
   http://www.teleport.com/~gregsa/curta/

Calculator Collecting  
   Webring designed to allow navigation between similar sites dealing with the hobby of collecting, and history of electronic calculators.
   http://k.webring.com/hub?ring=calculator

Soviet Calculators Collection  
   Pictures of calculators from the former USSR. Includes advertisements, articles, and a guestbook. English and Russian languages.
   http://www.rk86.com/frolov/calcolle.htm

Stellatron Calculators  
   An A-Z index of manufacturers, with product photographs, and a timeline of model releases.
   http://website.lineone.net/~lineup/st-pages/calcmain.html

Retrokit  
   Photographs of some older calculator models.
   http://www.tozzo.freeserve.co.uk/calc/calc.htm

HP-41 Archive Site  
   A library of information about the HP-41 series calculators, with emulators, publications, FAQ, and related links.
   http://www.hp41.org

Vintage calculators  
   A collector displays his small collection of old calculator models.
   http://www.netcomuk.co.uk/~wwl/cacls.html

The X-Number World of Calculators  
   A collection of articles about the history of calculators, mechanical and electronic. Also, a number of on-line calculators, recommended books, and a vintage collectors forum.
   http://www.dotpoint.com/xnumber

Vintage Calculators  
   Information and lists of vintage and classic calculators, primarily Hewlett-Packard and Texas Instruments.
   http://www.decodesystems.com/calculators.html

Casio FX-700P Programmable Calculator  
   Technical information about hardware, interfacing, and programming of this vintage device. Includes a construction project for a storage device to emulate the original FA-3 cassette interface.
   http://www.pisi.com.pl/piotr433/index.htm

Collection of Calculators, Portable Computers and Vintage Electronics  
   Calculators from the '70s, and famous home and personal computers from '80s. Photos, historic information and links to other resources.
   http://web.tiscali.it/city/

The Famous Slide Rule Page  
   Pictures and descriptions of The Castell Addiator and The Rapid-Calcolo.
   http://www.geocities.com/ResearchTriangle/Forum/7787/sliderule_collecting.htm

The Old Calculator Web Museum  
   Photographs of the exterior and interior of many vintage mechanical and electronic calculators. Also includes vintage advertisements and technical literature.
   http://www.oldcalculatormuseum.com

Calculator's Pages  
   A collection of early mechanical calculating machines and other calculating devices.
   http://www.calculators.szrek.com

Calculators 3000  
   A software simulator of Soviet calculators like B3-34, MK-61, MK-52 and others. Program is available for Windows OS.
   http://www.emulator3000.emuita.it/c3.htm

Using and Collecting HP Calculators  
   Information about various HP calculator models, with photographs. Includes instructions on using some of the special functions of some models.
   http://membres.lycos.fr/hpcalc/

Rick Furr's Calculator Reference Page  
   A collection of information about HP, TI and Curta calculators. Includes articles and many related links.
   http://www.vcalc.net

Reverse-Engineering the HP-75C  
   A wealth of information about the HP-75C.
   http://www.fortitudine.com/~coryc/html/hp75c.shtml

Old HP and TI Calculators  
   Photographs and information about HP and TI calculators, including many programs.
   http://www.rskey.org/gene/hpgene/

Texas Instruments 59  
   All about the TI-59 programmable calculator, with photographs and information about accessories, documentation and programs.
   http://www.ti59.com/index.html

Bring Back the HP 15C  
   Fans of the 15C want Hewlett-Packard to put it back in production. Find a list of reasons to bring it back, the reason it was discontinued in the first place, and an online petition.
   http://hp15c.org/

Calculating Machines  
   The private collection of the Dutch collector Nico Baaijens of mechanical, electro-mechanical and electronic counting, adding and calculating machines. Many pictures and close-ups.
   http://www.calculi.nl/

Anita Calculator Simulators  
   A collection of Sumlock Anita calculators and simulators, and related devices associated with the Sumlock factory in Portsmouth, U.K., in the 60s and 70s.
   http://www.lyvedon-way.fsnet.co.uk/calc/CALC.HTM