Hell, no. If you have a car just sitting in your garage, should you have to surrender it to the DMV (department of motor vehicles)? I've purchased many domains that I planned to use; but plans don't always work out. That doesn't mean I should have to surrender my assets. Yes, I'm frustrated when a domain I want is taken and I visit the site only to see a "search page". But that's the owner's option. Maybe all those dormant projects on SourceForge should have to give up their project names, too?