One of the funniest PowerPoint presentations I ever saw was in a Poetry course. I don't know how many of you are familar with Sylvia Plath, but she was a poet who killed herself by sticking her head in a gas oven.
Anyway, this guy in class had to do a presentation about her, and for the slide on her death he had a huge picture of an oven.
I don't know if anyone else finds that amusing.
I hate to be an Apple whore all the time, but the few experiences I've had with Keynote have been pretty positive. Some of the default templates are a bit more elegant, and so are the transitions. The cool thing about it is that you can export the slide shows to Quicktime, then import them into Final Cut Express/Pro or iMovie, then do voiceovers. It's a possible option whenever an editor's built-in text generators aren't quite good enough, and you can't afford to splurge on anything else.