$200-$300 beater bike. That is the most I would risk at most racks. If I am thinking I am going to be stopping somewhere, that is what I am taking out, not my $1500 and up bikes.

Although, the worst feeling I ever had was when I was a kid and I put my bike (some cheap 10-speed I got for my birthday, I can't remember the brand, I think I was 9 or 10) outside my house to use the bathroom, in the 2 minutes it took me to pee, some bastard took it and was gone. Don't you love NYC? But it taught me a good lesson, first off.. secure your stuff... second if it has any value, people are going to go after it. So I just leave the good ones home if I plan on leaving them unattended.