"waste of money" is probably one the most sad-funny things I've ever heard NASA called...it's funny that one would attempt to make an argument that spending so little money (comparatively) on such a promising program is too much. It's sad that so many think that way...
I found this link after about 5 minutes of searching...
http://www.thespaceplace.com/nasa/spinoffs.html
Beyond the extensive list above, there's the whole...galactic hazard thing they're good at keeping an eye on....asteroids, comets, black holes, solar flares, spacial radiation, the other planets (which Pluto is not), etc, etc....