Ever wonder how long you should keep important financial documents? Well here is a good place to start.

http://www.bankrate.com/brm/news/mtg/20000518h.asp

IMO, f you close a credit card, keep reciepts or actual statement for expensive items and/or any items for business/tax usage. Call your CC company and make sure they send you a letter stating the account is closed and the balance is $0. Then you can shre the remaining statements that you don't need.