Of course it is possible but why would you wanna do that and kill the bulb, and possibly do damage to the ballast, or worse. There is a reason they have certain ballasts for certain wattage bulbs. They match for a reason. I agree with you killer, it definitely is not a good idea. So don't get any ideas, seriously!

You could even run a bulb without a ballast, but that doesn't mean it is not dangerous. Quite possibly you could burn your house down. Personally, not a risk I am willing to take.