For those that want the official Silly Putty, you can by it in bulk from Crayola:
http://www.crayola.com/store/sp_index.cfm?dc_cid=194For those who do not know, you can buy it by the name:
"Dow Corning Dilatant Compound 3179"
This in even larger quantities.
There are more than just one color though. Here is a site that is worth checking out for, tricks, pictures and even purchases, an interesting site!
http://puttyworld.com/