How-to: Password protect a file?

My work laptop was just upgraded to Win7 Enterprise SP1 and MS Office 2010.

I've created a couple documents (Word and Excel) and folders that I would like to password protect.

Can someone tell me how to do this with Win7?

Thanks!

Possibly useful link:

http://discussions.virtualdr.com/sho...ssword+protect

Windows 7 Bitlocker and Bitlocker To Go
http://www.microsoft.com/windows/ent...aspx#bitlocker