On a MUCK I run, I decided to fake a mis-chan to see if I could get a reaction out of people... unfortunately, there weren't enough people to get something solid. Still, I felt I should share it:
"Okay, you'll need to make a Physical+Perform (Intimacy) roll against his Resolve. If you succeed, you'll get an extra die per Success on your roll to brainwash him. If you fail though, he's going to be... disappointed, and you'll be less likely to get him under your thrall. You might want to spend Essence, and do you have any gear which will give a bonus, or are you going to use any Retainers to help?"
In the rules, Retainers can count as 'equipment', and proper equipment provides a die bonus on skill checks. Now, while the set-up is silly, the mechanics for the entire thing is sound. Nobody's actually tried to do this IC, and I'd be highly amused if it came up, but... I had to try for the shock value. :)
Anyone else tried tossing out some mechanics that were sound, while the set up made people go guh?!
A prior time was on a MUCK inspired by Final Fantasy VII. We were talking on the staff channel about giant orbital satellite weapons which could run on magic, and a staffer had commented it wouldn't work -- so I developed an elaborate system which made it in-theme... and staffers who came in afterwards thought I was seriously going to run an adventure involving one -- it was that 'sound', both mechanically and setting-wise. I let them hang a little bit before telling them I wasn't going to actually use it.