I have a lot of old projects laying around in varying degrees of completeness, and I am finally going to put them all to bed so as to clear the decks for some new projects.
The first is a simulated annealing library (tarball or at GitHub). I wrote most of this on a plane several years ago. It is complete, except that there is an issue with the stop criterion that makes it often pass better solutions and end up on solutions not quite as good. This could be mitigated by writing the move manager to save the best solution seen, but the right answer is to just fix the stop criterion. Both it and the cooling schedule are very simple; my problem in writing an open simulated annealing library is that I know more sophisticated techniques for virtually every aspect of the annealing machinery, but frankly I don't feel like doing to research to figure out whether they're known prior art or whether we invented them at my past jobs (I've written several annealing engines before this one, and this one is extremely unsophisticated compared to those).
It's in C++. There is a Visual Studio solution and project, but no makefile; however, it's straightforward to compile.
I'm releasing this under what I like to call the "do the right thing" license. Which means, do whatever you want with it. No restrictions whatsoever. But please do the right thing. That means credit me. Let me know if it's useful to you, or if you make improvements to it that you choose to make open. If you use it in something that makes you money, maybe throw an Amazon.com gift certificate or something my way.