Monero is GPU mineable on both ATI and AMD.  Claymore AMD Miner is closed-source and gives mandatory 5% to developer. Tsiv’s ATI Miner is open-source.

Moneta Verde offers merged mining with Monero, QuazarCoin, Bytecoin or any other CryptoNight-based coin.

Technical Information
Release Date: 2014/06/17
Algorithm: CryptoNight
Total supply: Infinite
Premine: 0%
Block Time: 1 minute
Block Reward: log2(difficulty) * 2^40(difficulty)
Difficulty Retarget: Every block

Other Information
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