i'd say anything. you can pretty much use any speaker, and if you know how to use the global eq for the room you're in, you can pretty much make anything sound good/how you want it.
be careful asking such an open question on a gear forum like this.
you're going to get answers from people who spend all the money they can on their gear and from others who are on a budget. the budget answers will come out, and the big spenders will squash them down because their gear is superior, thus making you feel you have to get the most expensive gear out there.
"you can get a ______ for under $300 each!"
"but the woofer has too much 500hz in it. you need the ______, and they're only $1000 each"
"but i use the $300 speakers at home and at my gigs and everyone says it sounds great!"
"well obviously no one knows anything because they don't sound great, especially compared to the $1000 ones"
"oh, dang, well i guess i should get the $1000 speakers... sell my car and wife to get them..."
i woud suggest something at least 200 watts, maybe a 10" speaker. i personally use the k10 by qsc, but i've used the eon 15 g2, eon 10 g2, eon 515, yamaha msr, behringer powered speaker, yamaha passive speakers, computers speakers (yes for a small performance!), etc... and they all sounded "good" for what we did.
i only chose the qsc k10s because of the I/O panel on the speakers... very useful.
what is your budget? you say "cabinet"; does that mean you have an external power amp or are you looking for something self-powered?