What about an impromptu pumkin-modelling 'contest'? It'd be something a little simpler for everyone, have it finish the day before halloween, can just do a big thread / image of everyones' pumkins 'shopped together.
Looking back at the contest sub-forum for it it looks like it's turning out better than I remember. The last few times I've checked though nearly all but 3 or 4 of the threads had been posted in over the past 4 or 5 days. I guess people just aren't updating their progress as much as I thought they would be.