We like our "Suffer on Saturday" and have a lot of fun with it but your "Renegade Weekend" is a great idea. Run with it.
If you can't talk people into doing it with you shame them, post the results of those who do it on your blog and mercilesly mock those who bail. Let us know how it goes. Feel free to copy our "Suffer on Saturday" each month if you want. Send me your address and I'll put you on the mailing list, we send out a little post card each month describing the upcoming "Suffering". You could even send us your results and we'll post 'em. Round up a digital camera that will add to the fun.