I personally know your delima, often people ask for my skills at a late notice. John Palmers recipie for Big Basin American Ale can be pulled off in 10 days. I've done it. It definately is better aged for at least a week, however if you over look that fact, it is a clean crisp ale. I used liquid WYeast 1056 with a starter > 1.035 resting for 12 hours before pitching and was ready in 5 days for condittioning. Force carbed @ 38*f @12 psi for 5 days and purged to serve @ 7 psi. Aging while force carbing @ room temp would not be recomended due to the high psi required, you will spend all day purging wile trying to serve. Good luck!
"Dont worry Brew Happy"