Just found a $10.00 infrared thermometer. Is this worth having in the
toolbox?

Specifications.
Measuring Range : -33~180C (-27.4~356F)
Operating Range : 0~50C (32~122F)
Full Range Accuracy : +/- 2.5C, 2.5%
Distance :2~40cm
Emissivity Range : 0.95 fixed
Wave Length : 5um~14um
Power Supply : LR44X2
Spot Range: 1:1 (1mtr distance measures 1mtr spot size)
Display shown in Celsius/Centigrade & fahrenheit.

http://www.hobbyking.com/hobbycity/store/uh_viewItem.asp?
idProduct=8297&Product_Name=Turnigy_Infrared_Thermometer_
(-33_~_180Celsius)