Greg, my experience was similar to Stuart's -- it's great fun but after you use it for awhile, you pretty much know everything you need to know -- my pizza stone will get to 900F after an hour with all burners on full for example.
Harold McGee had a short note in the "NYTimes" yesterday you may find useful:
"By HAROLD McGEE
THE most important step in mastering heat is to get into the habit of using a thermometer to keep track of temperature — that of the food itself, and of the surface or space in which it is cooked or stored.
There are two kinds of thermometers that can help. I use both all the time to keep tabs on heat flow in my kitchen.
The common instant-read thermometer has a metal shaft that can be inserted into foods to measure inner temperature. Despite its name, this thermometer takes 10 seconds or more to give a reading that is sometimes lower than it should be because the shaft cools the food. (Warm the shaft before inserting it.) It can be useful in checking the inner temperatures of meats, fish, stews and sauces.
A more recent arrival in the kitchen is the pistol-shaped infrared thermometer. Point it at an object from an inch or two away, pull the trigger, and it instantly measures the infrared heat energy (even cold objects radiate some), converting that measurement to a reading of the surface temperature. It is instant gratification, and makes it fun to explore the thermal world.
The infrared thermometer is useful for checking the readiness of a cooking surface, like a frying pan or a pizza stone. It can also be trained on the various compartments of refrigerators and freezers, where the temperature determines how long foods will keep before spoiling. Most home refrigerators average 40 to 45 degrees, but they’d do a better job if they were kept colder. Drop the temperature to 32, and fresh ocean fish will last twice as long — for as long as a week."
I have the La Crosse Technology IR-101 Infrared Thermometer, which is a really neat little device. The biggest bitch: it uses four LR44 watch batteries which are a little tough to replace.
The folks at La Crosse are really good guys, with lots of fun toys:
http://www.lacrossetechnology.com/
I use my thermometer quite a bit to measure the water temps in our outdoor koi pond, primarily to double check the in water temps.
If you get one, you'll have a ball.