A useful tip picked up via an entry on AKMA's blog -- the tiny URL site allows you to create a "tiny URL" instantly from any very long one -- great to stop URLs wrapping in email messages etc.:
I'd seen these tiny URLs on David Meadows's Explorator and never realised what they were. AKMA also suggests trying your initials on the end of a tiny URL to find out what comes up, for a bit of fun. (Mine's useless -- /msg gets a dead URL).