
Originally Posted by
laura*
An orange Kryptonite lock in the smallest U shape would be great - I've heard it is a favorite amongst bike messengers. Their gray models are one step less secure but still acceptable. The yellow ones (i.e. NewYork) are awesome but spendy.
On Guard is another brand. To compete with the Kryptonite juggernaut, they use a little bit better technology. However, there are also many reports of keys breaking and/or jamming.
ABUS is another great brand, though they're mostly European.
No matter the brand, the smaller the U, the more secure the lock. Even the small U's work fine when locking to a bike rack. However, they might not work when trying to lock to non-traditional objects.