WR Usain Bolt
OK it's the offseason and I'm bored.
Obviously this isn't happening and I doubt he even has any interest, but I could see Bolt having the physical tools to be an elite WR. His 40 is estimated at sub-4 seconds. He's listed at 6'5" 207 lbs, ideally he could bulk up 15-20 lbs to a megatron-like physique so he could muscle up with DBs. The added weight would probably slow him down to ohhh let's say still by far the fastest human to ever play football.
If he just figured out a few minor details like catching the ball he would have the potential to be one of the greatest deep threats ever.