Like the WMRT SMD desoldering tweezers, the Weller WMRP pencil is a superb, German-made soldering tool. And like the WMRT, the holder that Weller sells is insanely overpriced and a good one can be printed for pennies (see http://www.thingiverse.com/thing:143780 for a WMRT stand). Both tools feature a magnetic switch in the handle which turns off the heat to the tip(s) to preserve tip life; when removed from the holder the tip heats to the preset temperature in just a few seconds.
This Thing features a recess for a 12.4mm x 5.5mm ceramic magnet; the sensor is quite sensitive so you don't need a fancy rare earth magnet. The holder is designed to screw onto a heavy base so it won't get knocked over (I used a scrap of 3/4" MDF and some stick-on rubber feet) and features a slide-lock so that the pencil can't be knocked out of the holder accidentally. It drops in and slides downward to lock - see the video here: http://www.youtube.com/watch?v=NOJmKYtiqRE&feature=youtu.be
The design can be edited on Tinkercad at https://tinkercad.com/things/dhjEEe5g69q-wmrp-pencil-stand.