Links

Video:

Hindu-Arabic Numeration System   (time: 2:36)
http://www.youtube.com/watch?v=gs4DCei79N8

History

This is one of the best all around sites that I have found. It is titled "The MacTutor History of Mathematics Archive."
http://www-history.mcs.st-and.ac.uk/~history/

This is an award-winning site that links to all sorts of mathematics information.
http://archives.math.utk.edu/

Reference Topics

There is an interesting site dealing with the abacus:
http://www.ee.ryerson.ca/~elf/abacus/