Redux: CindyH’s SOS: Co-Sign For Adult Child?

Have any of you co-signed on a loan for your children (18+)? Whether for a car, school, apartment. Do you recommend this?
I need to know before my son comes home at 11:00/ CindyH.

DFO: I’m rerunning this post from last night (7:42 p.m.) because it’s a great example re: how this blogosphere community rallies around one another.