Help with thinking of a duo name?

My friend and I are thinking of making a duo, but we need help thinking of a name. We're both female, and we're named Maddie and Mary. We were thinking of using M&M, but that's trademarked by the candy, and plus there's Eminem, which sounds similar to M&M. She'd play the keyboard and piano while both of us would sing. We'd have a variety of different sounds, like sometimes more soft rock, to pop, to techno, to electronic. Most of the time we're hoping to have an Owl City type of sound. Suggestions for names?