I'll start:

Long needle nose pliers - After I bought this truck I bought a pair of 12" needle nose pliers. I have needed them several times, but the job where they were crucial was the crankshaft position sensor, where the long pliers made it possible for me to disconnect/connect the sensor's plug. I couldn't fit both hands in there, but I could fit one hand and a long pair of needle nose pliers.

Shorty 3/8" ratchet - This is another tool I never understood until I used my boss' ratchet a few times. Mine is the craftsman with probly a 4" flex handle. It's amazing how often I use it. It speeds every job up substantially. These days the only time I use a full length ratchet is initial breakíng and occasionally final tightening. If you carry a short cheater bar, you don't even need a full size 3/8" ratchet.

Dremel - Just about everybody has one, but my #1 use is cutting stuff. I've used the cutoff wheel to the shaft on a shock absorber with a rusted nut. A few days back I used it to cut the front prop shaft centering ball in half after a torch and a slide hammer failed to extract it. Yesterday I used it to cut the heads off the rivets holding the plate under the center console. It's small enough to fit in tight spaces, and will cut almost anything.

Bluetooth OBDII scanner - At $20, this thing is a steal when cheapo scanners start at $50. Download the app called Torque, and the scanner talks to your smart phone and allows you to see all the info your ecu receives as well as read and clear trouble codes. You can leave it plugged in all the time, set up the digital gauges you like, and your phone becomes an ultragauge. I should probly buy a scanner for every vehicle I own.

 

Pump that screws on to the 1 gallon jug of differential lube.

Extending magnetic retriever with tiny light built into the tip

Decent volt meter

Infra red thermometer

Yard stick or very long screw driver - put one side against ear and other touch around suspect roatating parts. Try your alternator as practice. Or mechanic's stethoscope.

60 inch flat screen so you can see the RAVE in the garage, and monitor sporting events as needed.

8 MM 12 point skinny socket for valve cover snug up.

 

When you say "12" needle nose pliers" is the needle nose that long or the handle/arms of the pliers or a combination of both to make up the longer pliers length? You can probably get both, but which would work best for what we need here?

I was tackling some A/C work on my wife's minivan the past few days, and picked up a set of ratcheting box-end/open-end flat wrenches yesterday. GearWrenches is another name, or brand name for them. They came in real handy for a couple items I had to get too that would of taken me a good while with regular box-end/open-end flat wrenches, and could not get a regular ratchet with a socket in the small area. These are going in my D2.

I also carry a small/baby sledge hammer and a dead blow hammer both have good qualities and can be useful.

A multi-meter is a must, but one with a lighted display is so much better, and you can get the cheapy ones, and some of them have lighted displays. I first thought this was a waste, but I was way wrong.

I also just picked up a mini drill/driver, Ryobi TEK4 line at Home Depot. It is much smaller than my battery powered drill, and has become my go to tool for a lot of dis-assembly/re-assembly of items like interior, under hood parts or plastic wheel well panels with phililps / hex / torx heads. Bit set is included and it has a light that shines down the bit. Again, did not think much of this, but it is great. I picked up an extra battery as well. It is worth a look. http://www.homedepot.com/p/Ryobi-TEK...0#.UXtWa6ISEng

RAVE on your smartphone or whatever device you may have with you or in your vehicle.

 

With my pliers, just the arms are long. The plier head is about the same size as standard needle nose. Mine have a 45° bend in the pinchers, but you can also get straight or bent 90°. I don't think the bend matters much. I bought 45° because I figured they were in between 0° and 90°, and so could fill both roles.