Ask HN: How to make myself marketable?

I'm out of college this past year and six months into my first job. It's a steady career path with good benefits at a multi-billion dollar company, and I'd probably do well for myself if I stuck around.

It's fantastically unsuited for me.

I don't have any good horror stories yet about the company culture, but I have seen enough to know that this is not the environment and the challenges that I want.

In the last year, I've also discovered Stack Overflow, Hacker News, and a whole slew of new languages, paradigms, ideas, and possibilities. I've liked programming for a long time, but this is the first time I've been passionate about it, and my passion is growing. Now I want to find the kind of job that I'm thrilled about, not just satisfied with. Maybe the answer is to start my own business. Maybe it's simply to join a software-focused one that feels the same way I do. Maybe it's none of the above (indie/OSS development?). I only know that I need to keep moving.

I'm not in that great a hurry to leave my current job, and I'm told that such a quick exit isn't good future-planning, anyway. At the same time, I feel anxious to do more than read and tinker. I'm getting ready to start a blog. I'm busily polishing up my first app for release. I bounce my thoughts off anyone who will listen. I know I'm going to work on something on my own time, and I want to make sure it's something that will prepare me to get the best possible job for myself. So:

- How make myself most marketable to software-focused companies with the best cultures?

- How do I know which companies those are, and what makes them good?

- Should I start networking? What is the best way to do that?