Actually, to be a bit serious, I myself wouldn't mind a handy stack of "combat action" cards. My girlfriend is a very visual learner, and sometimes struggles to remember all her available actions in combat. (Heck, I sometimes get flustered DMing in the middle of an NPC-rich combat. Having something visual to reference in the heat of things definitely could improve my game.) My girlfriend would certainly benefit from the visual reminder, and it would help her feel way more involved in the game. And best of all, these cards could help improve role-playing all around. I mean, is there anything more mood breaking than, "I rush forward toward the orc with a bloodthirsty look in my eye. My mace drips with the blood of his fallen comrades...oh, and I'll take a five-foot step, activate my rage ability, and power-attack for full." Having these cards could be an easy and effective way to communicate out-of-game combat information without spoiling the mood or allowing for gross misinterpretation in intent ("Oh, how was I supposed to know that you were raging when you said you swung down with a mighty blow. I thought you were power-attacking.")
This, actually, is such a good idea for my table that I'm going to go design a set now. Call me the fool of this thread or whatever, but I actually think this is a good idea.