Yesterday we played 2 games of Classic Axis & Allies with a mod Ray added years ago. Ray made up a bunch of cards with bonuses. We pay 3 IPC for one or 2 for 5. The cards might give a bonus such as Battleships attack at 5 or a troop bonus such as one that gives Germany 2 Infantry, 2 tanks and 2 fighters in Berlin. You can sometimes, in fact often, buy a card that benefits your enemy. This in fact screwed us once as we were ready to go into Berlin and we bought a card at the beginning of UK's turn and pulled the above boost to Germany's defenses.
This game saw Ray and I as the Allies and Mugzy as Axis.