I don't like chains. I had a bike stolen locked with chains. My best advise is to get 2 locks. One which is a Club-style U-lock and one which is a heavy-duty cable (with separate lock).

Theives usually come equiped with cutters which will only be able to handle a U-lock or a cable, but not both (apparently, they are that different). You'll get to the point where you hate unlocking it, but it will be a deterrant for the others. Thieves are lazy, so make them work if they want your bike. The Club U-lock is nice because I've never met a bike stand it couldn't wiggle it's way around to lock both the frame and one tire (It may take some creative thinking on your part). Then you can use the cable to link the other tire to the frame and to the stand. Though I have not had a chance to take them up with it, the Club claims to provide a complete warrenty for your bike if stolen while using it.

If you can, don't put panniers or racks on the bicycle. I realize they are very helpful, but they are also are very enticing to theives.

I noticed an awesome lock recently. It looks like a set of handcuffs, and put out by master. It is heavy! but, I think that could make a nice 2nd or third lock.

I used the bike club for 5 of my 6 years at ASU, which is bike thief central. And I really want a pair of bikecuffs

What shape are the racks?