Nah, I couldn't narrow down the 12 I have.
My top 5 are:
1) Fluke 88 Automotive Meter.
This meter is any auto tech's best friend. It's accuracy and
features make electrical testing and diagnostics a breeze.
2) Ingersoll Rand IR3121 1/2" Impact Wrench.
I love this impact because of it's strength and light weight. It's
easy to maneuver and control in tight places.
3) DeWalt DW997 18 Volt Cordless Drill.
I find myself using this drill everyday, for both drilling
functions, and as a 1/4" driver. Very handy for times when a cord or air
hose would get in the way.
4) OTC Mindreader 3750 Scan Tool w/ OBDII Upgrade.
This is a very user friendly, inexpensive scan tool that I use all
the time. The OBDII upgrade also allows me to view the data stream for
OBDI Ford EEC IV vehicles.
5) Silverline Mityvac Vacuum Pump.
It's just your basic hand vacuum pump, but in my opinion, it's
priceless. It also makes testing and diagnostics a breeze.
Take care,
~Chris