I've seriously offered co-founder positions to two people. One is actively involved, but not as a co-founder. He's my patent/IP lawyer, and an old friend I studied CS with in college. He doesn't want to be fully involved in a startup for a variety of good reasons, but he's willing to take equity for a little private practice work. The other is a former co-worker who would be my easy first choice for CTO. He's considering it, but hasn't decided yet and I'm not rushing him. He has good reasons to hesitate (like baby #5 on the way).

I've also done some "matchmaking" through networking and introductions, but I haven't yet met anyone else I'm willing to trust with it, or whom is ready to go for it (there have been several candidates). So I'm not in a rush to find a co-founder, and not making it my first priority. If it happens, it happens.