Edit: I am writing the rules for our first design competition now. Expect the post about this time tomorrow. Due dates for contest submissions will be one week from the initial rules post.
I know at least a few Opponauts play Automation (which you should check out if you haven’t already). What I’m envisioning is a post with some basic specifications (e.g. sport sedan built in 1985 with a maximum price of $25k), and then after an evening or a couple days we post our designs and compare. It could be done competitively, developing a scoring system and ranking designs, or just for friendly discussion.
I know they do this on the Automation forums already, but I’d much rather do it on here since the community is much better.