I've got a really large dome tent (12x12x7) that goes together just like the little backpacking tents. I believe it's a Coleman, I got it at Sports Authority. I wanted a tent I could stand up in, and that's not easy to find when your 6'7"! I can toss a queen size air mattress through the front door, very comfortable. I believe it cost a little less than $200.
I've attached a pic of the tent setup at Ocean Springs Yacht Club during the Horn Island Hop. That's my 18 in the background with the new graphics.