That cotton muscle shirt thing sounds interesting. I've been thinking about binders a lot lately and well, you can't just mash 'em flat and expect 'em to go away, they just end up looking like boobs, mashed flat boobs. I was thinking, what about some kind of shirt that would flatten 'em a bit but also shape 'em more into something like pecs? Bio-men can have a lot of mass in their pecs, even guys who are not that muscular elsewhere.
The other sure fire method I know of is to do a lot of running, like a 5K every other day, that and weights will lower body fat a lot and just plain jiggle the fat off, lol it's true.