Syncing software.

I have 2 computers, and I use them equally often to program stuff. I'm looking for a sourcecode syncing software, that syncs souce code folders between 2 hard disks (or a hard disk and a flash drive) in a way that the latest edited versions prevail - much like what database software does, but I don't want to use a database software because I really don't need to and it's too complicated.

So, any suggestions on a good SIMPLE syncing tool?