[Zephrant]

I use a tapmatic 30x - http://www.tapmatic.com/prod_xseries.html

I picked up a used one, and it works great. I use it in a Jet mill for taping 1/4-20 threads in acrylic. They have auto-reversing as well as normal models.

The 30x is auto-reversing, has a clutch, and a micro-adjustment feature.

Zeph