If you ever go to Epcot and don't get to ride Test Track due to mechanical failure, write Disney Guest Services and let them know about it.
Back in 1999, my fiancee and I went to Epcot on two spearate occasions to ride TT and both times it was shut down. When I got back, I wrote an email to the Guest Relations Dept; basically explaining the situation and how much we loved WDW but weren't sure if it was worth going again (yeah right?) because we wasted so much time trying to ride TT.
Within two weeks, a CM contacted me and asked me for my park card (yes, I save them). Within a week, she sent me 4 One-Day Park Hoppers to compensate me for the time I lost when TT was out of order.
Needless to say, I booked my trip the very next day. I didn't really expect to be reimbursed, but it just goes to show that a little effort can go a long way at Disney.