Prompt community idea

So I was looking at a prompt community on LJ, and I was thinking it sounded really awesome until I realized it didn't work the way I thought it worked. Then I thought, I could create my own prompt community that worked the way I thought that one did!

Basically, my idea is that there would be a table of prompts, except that each prompt would be assigned a number and that's all you would see (though maybe some of the prompts would be initially visible, to mix up the mystery levels?). Then people would pick pairs of numbers/prompts, and I would respond via email or screened comment telling them what each prompt was. And then they would take the pair of prompts and write a piece based on that combination.

Hmm, after writing that out, I'm wondering if it would be better to have half the prompts visible and half of them not, so you would pick one that you knew you'd like and then the one to combine it with would be a surprise. Or you could pick two you knew you'd like, or two surprises, or any combination of the above. That might be more fun.

The way that comm worked was that prompt choosing was open for a week, then posting open for the rest of the month, with a masterpost at the end, so I would probably run this one the same way.

So, would anybody else be interested in such a comm? Enough to bother running it, maybe a co-mod so I could get some mystery prompts too? :D

ETA: Please see my response to pippin below for a modified version of the combined-prompt idea that I think might work better!