helpful desktop additions

iwantsandy
email reminder service

connotea
free online reference management, but also useful for those articles you do want to save

del.icio.us
a collection of favorites - yours and everyone else's

Read it Later (Firefox extension)
allows you to save pages of interest to read later. a 'staging area' for bookmarks

Google Browser Sync (Firefox extension)
continuously synchronizes your browser settings – including bookmarks, history, persistent cookies, and saved passwords – across your computers. also allows you to restore open tabs and windows across different machines and browser sessions

Pearl Crescent Page Saver (Firefox extension)
capture images of web pages

comment on these and add some more!