Not quite ready to do a CNC conversion? How about a cheap and fully featured DRO (digital read out).
Yuri, who writes the blog Yuri's Toys has created an Android App that does just that.
Using cheap chinese scales , an Arduino , a Bluetooth Module , and a few resistors you can have a DRO that interfaces with your Android tablet or phone.
Yuri's application is available from Google Play and has all the basic DRO functions, as well as hole patterns etc.