I disagree. It's dangerous to give a blanket statement that all the work belongs to them by default.
What work?
I've been in several situations in which I participated on other projects outside of work which used not a single work resource. It's too damn easy to claim you did it while on site or using work property.
That's why it went all the way to the board one time when I steadfastly refused to sign any agreement with them since the language was so overwhelmingly vague and if I patented a coffee napkin idea at home it was theirs. Nothing happened since I they could not afford to let me go at all.
I would prefer that nothing is decided in anyone's favor by default and must be proved in a court of law (no arbitration).
A non-compete agreement does not work for me as an independent contractor. Unless you pay me extremely well i'm not going to lock myself out of an entire market.
Ohh, and I guess that since I only work in Open Source it's kind of a moot point. It's rather funny when I explain that they don't actually own anything I make for them at all, and I don't either :)
What I said is what you do for your employer, in the context of this discussion around Terry Childs. Configuring routers and assigning administrative access controls to them is definitely not a personal project, even though Terry acted like it was. He even attempted to copyright his configurations.
Point taken on personal projects, and everyone I've worked for has been fine with the ones I've worked on, including my own meager and forgettable contributions to FOSS.