I actually think a gift is a nice thought. In my experience, it always comes paired with an apology. "I'm sorry." is nice. "I'm sorry, here are some flowers and that ____ I remember you mentioned you wanted." is even better.
I mean, let's face it, females don't typically do that sort of thing. Heck, when we're in the wrong, a guy is lucky to get an apology. But that's just my experience. Guys don't typically have the patience to hold the kind of grudges we hold.