Bikeregistry.com bike lock and chain is good! (And register your bike too)
I just registered my bike on Bikeregistry.com, but I've had their bike lock for a couple years so I thought I'd let you know what I thought of it.
It's very solid. I think the lock is a better design than the standard padlock. The bar is not exposed so there's nothing to cut! They also have another lock that looks even more secure:
The chain is quite beefy and weighs like 10 pounds. "3/8" PEWAG security chain, made in Austria". It's a meter long, long enough for me to wrap around my waist. After a few days of riding with it I didn't notice the weight.
If you are looking for mega chain lock, this one is great I think, and it's pretty inexpensive too ($34.95+ $.44 shipping) Bikeregistry.com also has a few other small products like a saddle lock wire for a couple bucks.
And of course you can register your bike for free on this site and get some stickers so the good person who finds it can contact you!
Anyone else use this site to register? I think I need to contact the police station to see what other registration I could do with them too.