I'll need to check what rate the Buterfly Labs cube from my son's stuff is doing. It's been on here since Oct. 11, generated I think about .25 bitcoin. Pretty good for a little 40 watt cube connected to an otherwise unused netbook. I contemplate plowing the proceeds into another one.
I received the PC he was trying to set up for a miner a couple days ago. 1200 watt power supply, gamer grade video card, fast Asus board, 3.4GHz AMD CPU, blah blah blah. I don't think he ever got it to quite work right. I do know there's an email to his landlord apologizing for inadvertently upping the household power usage 30% one month, from his miner.