The Dice-O-Matic
I personally like the "satisfaction guarantee":
QUOTE (GamesByEmail.com)
There is no doubt that I will still receive complaints about the rolls, but now I can honestly say I have done all that I can possibly do: the rolls you get are exactly as random as those you would get throwing by hand. As I promised earlier, if you donate to the site and are unhappy about the rolls, let me know and I will pull a die out of the machine, melt it flat and mail it to you, as an object lesson to the other dice. Tangible revenge.