The majority of people change their oil when it's warm. The reasoning behind this is that warmer oil flows/pours easier than "cold" oil and one would be able to completely drain the oil pan (or allow as much oil as possible to flow out, within reason).
That sounds about right. Either after I have been out driving for a while and let it sit to cool off a bit, or after 10 minutes of trying to get up my Rhino ramps.
its also better to change it when its warm to get more of the crap out with the oil. when the motor is cold, the oil will come out fine, when you drain it warm, you get more of the other deposits in there with the oil. at least thats what i slept through when Sears tried to tell me how to change oil.
EDIT: changing the oil like tyhe guy did in my sig is another accepted way of doing things........ anyone who blows their motor thinking thats the real way, darwin says hi.
that story in your sig reminds me of this dude on another forum who asked if he should mix a little bit of water to thin out the consistency of Lucas OIL stabilizer so he can put it in his gas tank.