RUSLAN 2 - THE CUSTOMS DECLARATION
Try the links below. Although we are told that we do not need to fill in a declaration unless we are carrying $10,000 or more in cash, it is not allowed to take more than $3,000 out again without having declared it on entry! (2011)

http://www.guidetorussia.org/russian-visa/visa_documents.html
http://www.saint-petersburg.com/russian-visa/migration-cards/customs-declaration.asp

Here you can print out a copy of the declaration in English:
http://www.customs.ru/en/ftravelers/DECLARATIONS/