good bike lock

Going along with the seasonal bike inquiries...can anyone recommend a good bike lock? I've got a Target gift certificate, but they only carry the U-shaped Bell brand locks for fifteen bucks, so I'm wary.

Kryptonite NY Lock. Throw away the shitty lock it comes with and get an American lock or one that has the multi lock cut keys. There are some u locks out there that some people use but those can easily be pried open with a crobar.

This is a good, cheaper option: http://www.nashbar.com/profile.cfm?category=102&subcategory=1120&brand=&sku=9232&storetype=&estoreid=&pagename=Shop by Subcat: Locks