Everyone should have heard of Iron Chef by now, but if you haven't, it's a cooking show contest where the chefs are told at the last minute what suprise ingredient they'll be using. This idea has been applied to various other competitions. For example, I've seen it used on roleplaying adventure design contests, short story competitions and, bizarrely enough, book reviews.
So to bring it all together, the idea would be to host some sort of art competition on gamedev, with subscription times as prizes. It would probably go something like: day 1 announce the contest, and name three elements that the art needs to incorporate. For exposition, let's say the color blue, the number seven, and the theme of "contrasts". Then start accepting submissions. Close submissions after a certain time period, maybe a week or two. Then do judging.
Judging would probably have three categories: how well it incorporates each of the themes, creativity and execution. The first part should probably be self explanatory. The second one prevents things like looking at a million pictures of angels and devils if one of the elements was good vs. evil. The third one would be that subjective how good it looks category. They probably wouldn't be weighted equally however.
I'm pretty sure that it would be possible to run all this on my own once we get the features in. I might want to think of some way to slant this towards game art ideas. And probably rope in a couple of other poor bastards to act as judges as well.
Depending on the prize scales, (right now I'm thinking a year to first prize and three months to a runner up) I could afford to do this perhaps monthly. Of course, the question would be whether or not we have enough artists lurking about to support a monthly contest.
In theory, the next step behind following up with this idea would be to talk to some staff members to see if they mind something like this going on. But in practice, before I can do anything about this idea one way or the other, I need to clear up some free time.