[jwwest]

Pretty common in BigCorp land. The problem is that many of these IP Agreements are very badly worded. The spirit is that you should not take work you do for your employer and turn around and create a product that directly or indirectly competes with them in the same industry.

I'm not sure how enforceable these agreements are. Like anything with our legal system in the US, they're used often to bully people into submission with the threat of legal action, regardless of the company's actual intent. In California, there's a wide range of employee protection laws in place that would make these difficult, if not impossible to enforce. Not sure about elsewhere in the country. (standard IANAL disclaimer applies)

One place I worked at had a pretty boilerplate IP Agreement. I worked with them to change some of the wording so it was less vague. There is often a section on these things where you can provide "prior inventions" that are excluded from the agreement. I took the opportunity to list every idea (as vaguely as possible) I might want to pursue in during the expected course of my employment.