Jay is right. If you interlink all those sites the same way amongst each other, you run the risk of being labeled a "network", and I have seen people penalized for that. (At least that is the conclusion some of us came to) If you do decide you want to create sites and link with other sites, your best bet is to link with other people, not just yourself. And don't make all the links on the sites exactly the same.
All that said, while I don't mind if the free sites have link trades on the bottom of the page, most LL don't allow it, so don't go changin' things and get yourself banned.
