I used to have a Myr deck that you could combo a Palladium Myr (tap to give +2 mana), and two Myr Galvanizers (Tap and pay a mana to untap all other Myr) to get

I used to have a Myr deck that you could combo a Palladium Myr (tap to give +2 mana), and two Myr Galvanizers (Tap and pay a mana to untap all other Myr) to get infinite Mana. Combo that with any number of cards (X mana to do X damage, or X mana to make target player draw X cards, etc), and you get a fun way to win a game (though hard to pull off).