I was playing with some crackme template and decide to make small keygenme. Objectve of this crackme is to make valid keygen. No patching! Algorithm is very easy.
File is packed (you may get virus alert from some AV programs) and this could make things harder, but packer is already reversed on this board.
I tested it only on Win XP Pro SP1. Also, I didn't crack it myself so it is possible that thecrackme has bugs.
That's it, enjoy. Pass for rar archive is "clone" (without quotes).