The last two posters I've done have had mandatory logos to put in. I usually don't have too much trouble with this kind of stuff and just cram everything at the bottom.
This poster is for a cool Second Life project based out of Williamsburg that I'm currently interning for, called Brooklyn is Watching. I kind of suprised myself at how easy it was to make something a little less hairy for once. Maybe I should work for Lavalife.