You know, you don't have to give up the "safety and security" of a full-time gig to have the freedom and control-your-own-schedule benefits of a freelancer. The "Results-Only Work Environment" ( http://www.gorowe.com ) is trying to merge the stability and benefits of a full-time job and the flexibility and freedom of freelancing. If more gigs embraced ROWE, perhaps folks wouldn't have to choose the lesser of two evil…
Not sure about the average freelancer, but most technical freelancers I know see it as a stepping stone towards getting their own little SaaS or iPhone app business off the ground.
If you're working full-time for a company, IME contracts tend to own all intellectual output at your time there, at home or otherwise. This doesn't matter much if all you do is put out MIT licensed experimental programming language parsers, but I wouldn't put many companies above executing on those terms should a product you build in your off-time achieve success.