T-Cat,
I had used my pinky for chords only until I started with the band at 16. As I was a bit annoyed by the lack of flexibility I used a very simple exercise to improve it.
Place you index at 5th string 2nd fret and play the following

e-----------------||
b-----------------||
g----------------o||
D----------------o||
A---2-4-5-4-2-----||
E-5---------------||

an advanced version, the index remains on A2 or even more advanced barre 2nd fret :

e---------------------||
b---------------------||
g--------------------o||
D-------4-5-4--------o||
A---4-5-------5-4-----||
E-5-------------------||

Be careful when doing such exercises as it can hurt pretty bad if you're doing too much. Stop immediately when you're feeling any pain. Relax your hand and get back to it later. It's quite possible that you can only do very few repetitions. That doesn't matter.
I'd recommend that you play your usual pieces and between two pieces train your pinky for a few seconds. It's easier on your hand and it's less boring than doing scales for an hour.
None the less, the way you approach repetitive exercises will determine your success. As your not the most patient person in the world it's not easy to work that way, but try to see it as a kind of meditation. Once you've mastered the basic movements you can relax your mind and just listen to the sounds. I would think that you have experienced similar things on the bike. When you're alone on a long straight road and there's nothing but the sound of your wheels and the monotonous rhythm of your legs, you sure had those meditative moments where you're not really thinking at all. At least I did pretty often. :)

Marcel