You have to be careful when going through all of the advise that you'll get on here. Some may seem like really good ideas, and *some will just scare you with a perceived danger. But, I will have to be honest with you. The fix for this is terrifying. First, get your insurance card ready and a really small belt, have someone standing by to run you to the ER if the worst happens, as expected. Then take a 16" chainsaw, place it in your lap and crank it. I always have to prime it first, but that would depend on what brand you have. Avoid electric saws, as they don't usually have the brakes that the gas one will have, and sawing half-way through your leg is always better than all the way.
So, crank the saw and grip the stem with one hand firmly, as you don't want the force to throw the stem to get ripped out of your grip and slam against a wall. This is where vicegrips rule. Tighten those mothers up snug. Ok, cranked saw, stem in vicegrips, now carefully remove just a hairs width of stem. Next, you'll need a tourniquet. Use the small belt to prevent too much loss of blood before someone can get you to the ER.
The last step is to enjoy your pipe as you relax on your way to the ER.
*Warning, this method should only be attempted by the most experienced of pipe smokers. :
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