well..if someone is really a fan of racing, usually they would focus on one type, such as nascar, F1, etc and incorporate that into the name.. I know racingcar sold for 18K, but that doesn't mean anything realated to it should be worth more automatically, racingcar is a good domain, but I don't think its worth 18K either, looks more like the buyer really wanted it for some reason..the name is pretty long too and I think the plural of this domain is still available, so I think the above estimate of $50-250 is pretty good, if at all I would say its at the low end of it...