A so-called "cash for clunkers" program was appended to a military spending bill and passed by Congress on Thursday. It really is a pretty lame program from an fuel economy point of view, as is demonstrated here as part of a larger rant. Of course, fuel economy wasn't the primary driver of the program - increasing car sales was. And like most poorly thought out government programs, there are plenty of unintended consequences.
Could a good trade-in program be designed? Probably. I've been noodling on one but the futility of it all is overwhelming me right now. Maybe I'll haul my plan out some other day.