Sorry about all the "blogs" in my title. But anyways.. I am thinking about making a blogspot blog to blog about the updates i do on my main blog. Each blogspot post that i make will have a link to my most recent post on my main blog. This sound like a good idea? Or a spammy and "already tried" technique?
I don't think it's spammy. It's just that you'll be working double for that. The benefits you'll get can be sufficed anyway by link trading. But if you're going to optimize the new blog too and put some money making things on it, it's just like making a new blog...
Also remember that Blogger has its own API so you could develope some scripts to automatically update the secondary blog. I've tried this before with some results