This picture of Thorn as a member of the Sinestro Corps was done by BertyJA as part of a series of his where he makes characters into various superpowered Lanterns. I'm honestly not really a DC fan, and all I've seen of Green Lantern was the pretty bad Ryan Reynolds movie, but the picture is really nice.
Check out his original submission on DA here:
http://fav.me/d7ezutx