Ask HN: Free or very cheap marketing suggestions for startups

For a small (1 person) startup without any funding and looking for marketing strategies, what do you suggest?

I came up with a few ideas that I have been using lately, but would love to hear from you all.

My ideas:

-Register on forums/mailing lists that are close to what I am doing and start participating and when possible pointing out my product. I am noticing that sometimes with a good answer (even without pointing my product), people will follow the link on my profile ...

-Switching the referrer on my browser to always point to my domain ... Ok, I did that a while ago I am seeing people going to my site from their awstats/webalizer pages, but don't know if it can cause damage at the long run (just trying).

That's it...