WebCL Firefox Bitcoin Miner
kradminer.com
kradminer.com
But keep in mind that the reward for a block is currently 50BTC, so if the calculator shows 0.1 BTC/day it will take 500 days on average to get anything. Considering that the difficulty will increase rapidly, that actually means you will most likely never see any BTC from this.
edit: tried it, looks like this is actually group mining. The author is collecting all the BTC, and promises to give you your fair share each day. He should disclose how much he is pocketing for himself.