[JohnFen]

> Would my current company have an IP claim on my project if I use it at work?

Not because of that, no. However -- depending on the terms of your employment -- your contract may have one of those nasty clauses that give them IP rights to anything you develop during your employment. If that's the case, they may have a claim based on that and that claim would apply whether or not the software was used at work. Those clauses are the first things I look for and negotiate away when getting hired.

My advice is to talk to an attorney about all this. A short consultation shouldn't cost a fortune.