I figured this might be the place to post this. If it's not appropriate, feel free to ignore or delete it.
I came across a link to this challenge the other day:
The Free Will Hostel: Hands Off Challenge. I thought it was quite interesting. As a matter of fact, I'm in the middle of playing an altered version of it as we speak.
Basically the premise is that you enter 8 sims into a lot (there must be two married couples and a couple siblings in these), and furnish the lot however you'd like with a budget of 250,000 simoleans and then walk away and let them manage themselves for 5 or ten
Real Time hours. You can save and resume the game later on, but the gist of it is to see how well you can plan your home so that your sims can at least keep themselves alive.
I must say it's interesting flicking back and forth from the game to other things and then coming back to find one of one's sims pregnant with no knowledge of who the 'father' was. It makes it a little more dramatic and exciting.
ETA: It's similar to the Sit-On-Your-Hands Challenge, just a little more extreme.
ETA2: Duh. I didn't even notice that this challenge was linked to in the previously mentioned challenge thread.
Oops.