A light illuminates on your dashboard. "Oh, I recognize that one", you think. Maybe you choose to ignore it, or maybe it is an easy fix, it goes away momentarily, days later it happens again. Is it a wiring mishap or is something seriously wrong? Your mechanic might charge you $100's to figure it out, or you can do it yourself with CarMD, a handheld device that works with cars newer than 1996. Coupled with an online database, the device provides you with information only your mechanic had; until now for only $98.99.

When the team at CarMD gave me a sample device at Macworld 2010 I had planned to check it out the next time my car acted up. As I just "invested" over $5,000 into it, I had hoped that was not going to happen for a while; a few weeks at least. Unfortunately, a few days later, my check engine light turned on, so I figured it was time for my review...