Yale University offers a series of their courses online through their Open Yale Courses program (videos of lectures, notes, etc.), and the game theory course with Ben Polak is quite good. It’s a nice resource for refreshing one’s memory (or starting from scratch if so needed).
Update: I posted this in a hurry yesterday as I wanted to share the link with colleagues. Let me just add that of the lectures I’ve viewed online, Ben Polak deserves credit for being an excellent lecturer. He’s charismatic (which is always nice) and has some nice tricks for conveying the subject to students (much class participation). On the technical side, the video and sound quality is excellent.
In sum, I would be completely comfortable directing someone, even those completely unfamiliar with game theory and afraid of formal models, to these videos confident that they will get something valuable out of them.