Interesting reading:
http://community.wizards.com/go/thread/view/75882/19686254/Rules_you_didnt_realize
We do get most of these right, but there are a few gotchas there for people going from 3.5e to 4e. One that I didn't realise was that you only get three death saving throws between rests: not three for each knocking-out you receive. I don't think Rhaakor has ever cheated death in that way, but he has perhaps been a little bit too brave...

).