Last (Wo)man standing

I've seen a few groups and different challenges posted on here and have been considering starting one. I need something to work toward and people to compete against. I believe it's possible to make a private group which is my intention. I'm thinking of doing the typical time period of 12 weeks - Nov 1st to Feb 1st. (Selfish reason - my birthday is in Feb).

Here's my plan:

-Everyone sets a realistic goal(s)
-Weekly challenges are set and someone wins (Dunno what)
-You can be kicked out - that's right, fail to meet expectations (i.e. log daily) or get three strikes for doing same..or similar...get your *kitten* booted out.
-? ideas

I'm still in planning mode...ideas would be appreciated or if there is any interest, post. Fitness level and goals don't matter but some challenges will be harder than others.