Yes, I use it as much as any of the others probably.

I second Chris' suggestion to play using your middle, ring and pinky fingers only. I used to do an exercise where I'd play a scale with those three fingers and have my index finger behind the neck. Not sure this position is very wise looking back, but it did help my dexterity at the time.

The pinky is a problem because from my limited understanding of anatomy, it shares a tendon (I dare say someone will correct me here)... so it's not easy to move it independantly. As with everything else, practice makes perfect.