Any one mention Youtube? Making videos for that site is also a good way to get traffic. Maybe some instructional videos?
Some people swear by traffic exchanges. Posting in the correct category is good for targeted traffic, they say.
I have 39 followers right now on Twitter and it doesn't translate into much traffic. But how about the search engines? When I post to my url to Twitter, does that count as a backlink in Google? How about facebook?