Storing Pizza Stone in Oven I have heard that you can leave a pizza stone in the oven all the time, essentially storing it there.  What are the considerations to keep in mind when doing this (type of oven, placement of stone, etc.)?  I currently have a gas oven with the element located inside the broiler drawer below.  Can I put the stone directly on the bottom of the oven, or should I keep it on the lowest rack?  Are there reasons to remove the stone from the oven, if you're cooking certain things?
Actually I do this, and I do it because my oven is old and tempermental. 

Adding a heavy heat-sink (like a pizza stone, or a half dozen fire bricks) to your oven will increase your pre-heat time, but it makes your ovens temperature much more stable. It's a good thing to do if you're planning on cooking anything that is really temperature sensitive.