Small claims doesn't apply. By the act of purchasing a ticket, you agree that any and all dispute between yourself and Megabus is to be handled by an arbitrator. it's a lot like releasing a hockey team from damages caused by flying pucks.
Now, in practice and in a real court, that shit doesn't fly. Seriously, it's unenforceable, and we absolutely can sue, and probably even win. You cannot simply recuse yourself from all liability and force a person to give up their right to sue. However, in the context of a small claims court, you may as well have done so - small claims will historically ALWAYS back the person who set the terms and conditions of a contract, regardless of their legal validity. We'd have to go to a REAL court to get a judgement in our favor, and a real court and real lawyer are going to cost us FAR more than we'd ever get back, even with punitive damages added in (a quick check shows us unlikely to break even unless we get into the high 6 figures of punitive damages).
So unless Megabus actually does what they said they would in the news broadcasts and reimburses us fully (which I'll believe once I've cashed the check and it's gone through), we're essentially screwed with no recourse.
Dan, you've met my mom. She used the term "legally fucked without lube." That should probably tell you something.