What is code worth?

As a software engineer, I write lots of code, and as such, I have thought a good deal about how much that code is worth. Most of my code has been written either for a class project or for my official duties on SGA, but I could also take that code and market it, but at what price? In the normal world of economics, there is a mathematical cost function for figuring out how much a widget is worth, but software is a new beast. When I spend many hours working on an application or library, is it worth some hourly wage times the number of hours put into it? I could have spend 50 hours carving a toothpick from a 2x4, but is it worth $50/hr * 50hr? There is also the problem with unit cost, the price of software is, for analytical proposes, 100% developmental. The pricing of most software is seemingly arrbitray, the company sets a price based on what they think people will pay, but now 'stealing' software takes a new twist; when I steal software, you don't lose anything.