I generally prefer to ride alone.

Folks may scoff at the big honkin' bag I always have on my bike, but I've got the stuff I need (and sometimes the stuff other riders I find stranded along the road need, too!)

Road ID, wallet, phone, regional bus pass, ALWAYS. If I get into a situation I can't get out of easily with those, I also have Better World. They are an auto club (like AAA only a lot cooler) with bicycle coverage.

Better World Auto Club not only covers bicycles, they also give a discount if you use mass transit. http://www.betterworldclub.com/

Oh, and if you consider yourself a family, they give you the family rate.