Ask HN: How do you make sure you don't stagnate in your position?

I've been working in a .NET shop for 3 years (since graduating), and I'm looking to get away from that. But almost every listing I see that isn't .NET requires experience in their specific set of technologies. I could probably take a lower-paying position that assumes no experience, but would rather not for obvious reasons. How do you balance being compensated as an experienced developer and not pigeonholing yourself into a specific set of technologies?