If budget isn't an issue... some of my favorites with my company have been...
Trip with everyone to Chicago, NY, LA, Vegas or Miami see a show, go shopping, cover all expenses for the team, etc. Shopping spree at Easton: Give out cash and you need to spend it all within a set time. Meet back up and have a private dinner and share stories of what you got. Scavenger hunt across town. Big prizes for winners of various legs.. TVs, laptops, jet skis, etc. Team bingo... big prizes make it fun.