Actually an air nailer is a very small load and will run on just about any size compressor like the $100 pancake. The things that need big compressors are the impact wrenches, grinders, etc that run a lot, a nailer is just a quick burst and thats it.

Something like http://www.lowes.com/lowes/lkn?action=productDetail&productId=201991-70-D55151&lpage=none is what I wish I would have bought, small but oil type and after we move I'll be selling my pancake, probably at a big loss, to get one. The pancake meets my needs, its just I don't want to sound like I'm using a jackhammer every time I want to stick a couple lbs of air in my tire. Was a simple mistake of trying to be cheap.