Nintendo Expansion Pak for DS Browser + M3 Real

Can I do anything good with this setup, like play GBA games?

Don't think so, you'll have to have a GBA expansion pack to go with your M3 Real.

The only thing you can use it for the the Opera Browser for the DS, it can't be used for GBA games.Good thing is the EZFlash 3 in 1 can be used for the expansion pack needed for the DS Browser, and to play GBA games, and the rumble feature.