Sound system recs please!

Does anyone have any suggestions for a decent portable sound system? I need a new sound system for my Zumba classes. I'd like to have something that isn't too difficult to transport around (since I don't have my own studio yet) and would sound decent in a basketball court-sized gym. I've been looking around at various websites (where I tend to get distracted by best effects pedals and stuff) but I'm not sure what would be ideal. I've asked other Zumba instructors and, of course, they all recommend something different. Help!