If you are a wage employee (paid hourly) then you should get extra compensation for your work. If you are salaried, guess what, you're always on the clock. The idea being that certain types of employees aren't just working during work hours, you're often thinking about problems driving home, etc. This is why many companies have a form you sign when you start work indicating that anything you develop at work or away may be the property of the company. That said, managers always have leeway to grant spot bonuses, good raises, etc. Talk to your manager. If she/he isn't willing to work with you, don't give them the software at all. I'm guessing they are probably willing to meet you half way.

You should have read the articles more carefully. The /. summary was a poor one. It's a known, common fusion reaction used in many neutron sources...hurl deuterium ions at a deuterium target and you get helium and neutrons. The novel bit is how they accelerate it. They use pyroelectric materials to ionize deuterium gas and accelerate it at a target. This new method eliminates the need for large hi voltage sources, etc. allowing for miniturization of the system. (the prototype is about a foot long and a couple of inches in diameter but they are saying it should be little trouble to shrint the length of the cylinder to a few inches). Also, the reaction is started by chilling the unit slightly (even ice water should be enough) and then heating it to room temperature. It's allowing for smaller, safer, less expensive neutron sources.