Frank Cho has made a cottage industry of spending an hour or two creating sketch covers on blank variant covers and sold privately or on eBay.
By turning them into parodies of current comic book tends, transgressing one mores or other, combined with the usual good girl tropes, he's received criticism along the way, but it certainly hasn't stopped him.
After all, for one or two hours of work, he can get the likes of this…
That's an $800 an hour going rate… and helps subsidise some of his more personal work like Skyborne for Boom Studios. Here's a look at some of his other recent work, with and without wheat cakes.