I got the Thermaltake 560w PSU, it's awesome.
Got my 35w 2400+ XP-M OC'd to 2.5GHz
Got 4 hard drives
9 case fans, one home made PCI slot fan, a vantec Tornado as my CPU fan and 2 fans in the PSU for 13 fans total (you gotta consider the PSU fans since they do take the same amount of power as all the other normal 80mm fans you'll have)
lol trust me that PSU will take quite a bit, I still haven't noticed a drop in the rails either so I don't think I've even really taxed it that much at this point but I'm sure it's pretty close