When I respond to these things I am never sure where it is going to appear in the heirarchy (outline).
Anyway my answer is a surprise even to me. It is a $20.00 Li-ion screwdriver from Costco. Durofix is its name. I knew I used it all of the time. However, I found out how much I really like it when I had to do without it for a couple weeks. My Costco didn't have them. I had my son, Glenn, looking. I tried other stores. Finally my store had them again. Man I was REALLY glad to see that little guy.
It is ergonomically grreat. Has more torque than you would think such a small "toy" could have. It runs at full guts until the last 4 or 5 seconds. When it hits its max torque it does not fight, jitter, or anything like that...it just, gently stops.
Since it is sort-of like a drill (it has a handle and goes round and round) I am going to side-step and mention how much I like my 12v Ridgid drill. It makes my Firestorm feel and act like a piece of junk. It is much lighter than the 18v that I use and so it is more comfortable. It seems to have as much power as the 18v (Firestorm and HF) and in tight spaces or overhead it is much more comfortable to use. It has the easiest chuck to operate that I have encountered.
By the way Glenn, don't hit anything tender with that 10oz ballpein hammer.
Enjoy
Jim