I use a Mackie 808S mixer and a pair of 300i speakers on poles. SOmetimes I'll use my EV Sb120 sub woofer for larger spaces. If the place is real small and especially if I'm solo I'll use my Kustom KM100 keyboard amp and try to get it at least chair high.

I once played a bar/restaurant gig where I had to place the Mackies on the floor AND face them toward the wall - now that's getting into tight places.