I use twitter
I use it as a networking tool, where I chat with other affiliates, affiliate managers, etc.
I use it as a learning tool, where I ask the world at large all my seemingly dumb questions.
I also use it to feed every article I write on every site i own onto. That gets them crawled, indexed, and trafficked, all on auto pilit. I talk an awfully lot by nature, so my constant chatter outweighs the possibility of this looking spammy

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I also occasionally offer things on twitter, but only when I myself think they r just to good to pass up. I don't really go for the whole spam thing, most ppl on twitter won't tolerate it anyway.
All ya have to do to get rid of spam is rt the spammers user id with to @spam

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