Free (although limited functionality) tax preparation software

http://www.taxact.com/

http://www.taxslayer.com/classic.aspx

http://turbotax.intuit.com/

Rainbow tables

Rainbow tables are used to find the original plaintext for a hashed password. The password can be hashed using different hashroutines, where the most common are MD5, LM and NTLM.

http://www.freerainbowtables.com/

http://www.freerainbowtables.com/en/faq/

Invite sharing sites/Get Invites to Closed and Beta Sites

http://www.inviteshare.com/
http://invites.mashable.com/

Firefox privacy add-ons

Stealther https://addons.mozilla.org/en-US/firefox/addon/1306

Distrust https://addons.mozilla.org/en-US/firefox/addon/1559

Flashcard learning tools

http://www.opencards.info/