Things that are good (especially if you're in the UK)

QI (Quite Interesting) mp3s up for grabs. Works really well as audio, though best listened to while ironing, rather than on the train where people will stare at the crazy person trying not to laugh.

Season one.

Season two.

Season three.

Season four - this one, I'm still uploading the mp3s to, so it's a work in progress. 1-5 are up there already.

It's random information and occasional bits of Stephen Fry getting stroppy about grammar! Incidentally, the out takes for QI S1 are up on youtube, and definitely worth seeing.

Also extremely cool is this, the Old Bailey's criminal records. Searchable by location, name, time, crime, crime type and going back centuries.
Worth noting, by the way, is that sodomy used to be a general term for "unnatural acts", so some of the early indictments for sodomy were... yeah. Very interesting stuff and a fun way to kill an afternoon.

Also interesting is the Historical background stuff, which includes community histories (black communities, gay, gypsy/traveller, Irish, etc.) and tips for finding them in the proceedings, keywords to look for and so on, as well as stuff on gender, London and so on.

Final brief thing, Walkit.com is an excellent thing.