Not to beat a dead horse
But aside from the dropemembered (frame laying) trucks, a simple lowering job also seems to be adding value right now. I've seen trucks that would sell for 3-5K max bring 8-11k+ with just drop spindles, springs, and a set of 20" wheels. So an approx 2K investment is raising the cost 5-6k+...(assuming you do the work yourself)
It's not everyone's style but there are people out there who like that look and are willing to pay for it...(and want it done already...they don't want to build a truck)