Even if you signed a PIIA, double-check that it's enforceable where you are employed and is as far-reaching as you think it is.

For example, the California Labor Code stipulates that regardless of what an employment contract or PIIA says, an employee owns the copyright and patent rights to his inventions if the invention is made entirely on the employee’s own time, without using any of the company’s equipment or technology, as long as the invention (a) does not relate to the company’s business, or (b) did not result from work performed by the employee “as an employee” of the company. Washington and other states have similar laws that override any contract you might sign with a company.

An attorney in your jurisdiction familiar with this area of law can give you all the answers you need in just a few minutes for a nominal fee.