Toolmonger has discussed the value of having a soldering iron in the shop, and many Toolmongers mentioned Weller as a good make to have on your bench. If you want to take that iron off the bench, Weller offers the ML500MP, a portable soldering pencil.
You fuel the piezo-ignition soldering iron with standard lighter butane. The adjustable flame allows you to set the tip to between 750 and 900 degrees. You can get up to 30 minutes of operation on a medium setting. And when you remove the tip, the ML500MP functions as a small torch.
The flat base allows the pencil to stand on end for safety and work. It provides a light, portable soldering solution — you might use it for heat shrink applications or to fuse nylon rope.
If you dish out the $13 street price, you can take your soldering on the road.