Ken Krupa has been creating custom programming in AutoCAD professionally for almost twenty years:

DTI Technologies 
Creator of ADT Productivity Pack and AutoCAD Productivity Pack. Custom applications for a variety of clients.

SK Software
Principal of firm, creator of SK Utilities and ADA Design Assistant. Custom applications for a variety of clients.

Softdesk
Application developer contributing to Auto-Architect, plus various Productivity Tools.

The Mead Group
Years of experience "in the trenches" creating architectural working drawings and solving real life AutoCAD problems with custom solutions.