[clydeturbeaux]

Look up "key extractor" on the web (usually in a locksmith forum). They make a few different kinds of them, one is like a serrated wire on a handle which is inserted along the side groove (broaching) of the key. You bend it slightly sideways to allow the serrations to grip the key as you gently pull it out. Once it is even a little bit out of the cylinder, it can be grabbed with needle nose pliers and removed. The other type looks something like a gaffing hook and once you see an image, you can easily make one from an old hacksaw blade with a grinder and some patience. This type is usually inserted along the top edge of the key and may take a little rocking motion to lift the pins/tumblers as it makes its way past each one. You can usually hook one of the key cuts and gently withdraw the broken piece. In both cases, it is imperative that the lock cylinder is in the same position it would be in when the key is to be removed. If you can rotate it to this position, you are almost guaranteed success. I've even seen welding torch tip cleaners (the kind that are folded up like Allen keys or a pocket knife) be used. If you can find a friendly locksmith, they may even loan you the tool with a monetary deposit. Good luck- it's actually easier than it sounds. Be sure to post up your success story once it's out!