We do one over at Mantidforum each year and it is a lot of work. In years past we have scraped a calendar or two together here on Roachforum, but I can barely keep up with the approving of new members against the spammer database between the three forums, these days. If somebody wants to volunteer to put the calendar together once the submissions are all in, I think I can work alongside that individual to make this happen. It's actually quite easy to follow the calendar template instructions. My thought is to create a new section of the forum and temporarily promote a volunteer to moderate that section of the forum through the contest (to make sure that people are following the rules from beginning to end with respect to photo requirements, for example).
So, thanks to Dubia Dynasty for the suggestion. We'll hold this thread open to any volunteers that want to be considered for helping out with the contest (i.e. doing most of the work), and gauge general interest along the way. Since it has been a week and a half since you posted the idea, I would like to see a few more members posting in this thread to indicate their interest in participating. I guess I should quickly say that these calendar "contests" consist of members taking decent quality photos of their pet roaches and submitting them to an open thread (as yet to be created). If we get more submissions than months it does become a contest where members vote in the best 12 photos.
More details to follow (if interest warrants it)...