Here's a late round or even an undrafted Free Agent prospect-
Imagine a 6-2, 230 lb Running Back who consistently runs a 4.40 40 yd dash. With size and speed like that you could convert him to a WR or TE.
He's the Canadian college Heisman winner.
http://slam.canoe.ca/NFLCFLFuturesOnTheRise04/1018.html