A friend of mine here in Tokyo owns a small music company and recently launched a series of games to help with music training. They are flash-based, but I have been quite impressed with them and have enjoyed them quite a bit! He is using a freemium model, and you can try out the games on his website without even registering. (Free registration gives you progress tracking, and subscription gives you access to all levels and games.) For anyone interested in music training, I highly recommend them!