It's not a compiler, per se, and it's a bit time-consuming, but check out this node from tye. It should explain how to do what you are looking to do, no purchase of anything required :)

If, however, you require an opaque binary, then I suggest you follow Merlyn's advice (from the Llama book): "The real way to keep your secret algorithm a secret is, alas, to apply the proper number of attorneys; they can write a license that says 'you can do this with the code, but you can't do that. And if you break our rules, we've got the proper number of attorneys to ensure that you'll regret it.'"

Hope this helps,
MrCromeDome