There's a discussion on the Ravelry Men Who Knit group about knitting too tightly, with guys talking about whether they wrap the working yarn through their fingers. I wrap the working yarn around my pinky, as you can tell in this detail from my Halloween costume:
Here's what the black rubber gloves are hiding: my pinky is actually quite misshapen.
I noticed my crooked pinky when I was about 10. I had trouble spreading my hand beyond an octave in piano lessons, and I had trouble pressing the keys on my saxophone that would let me hit the lowest notes. Beyond that, it's never really bothered me. It doesn't hurt (although I do remember a couple occasions when it has been mysteriously numb), and with the rest of my fingers relaxed and curled, it's not really noticable. I think it might even help with my typing (as long as I don't have one of those nasty "ergonomic" keyboards).
My mom's parents both had gnarled fingers, my grandmother from arthritis and my grandfather from a childhood accident that crippled his hands. In some ways, my grandfather's hands are how my family came to be. As capable as he was, his hands kept him out of the war (he tried to conceal them when volunteering, but they were discovered, and he was declared 4F). He stayed home then, and married my grandmother; my mother is from that small generation of Americans born during World War II. Even though my grandfather's hands were shaped as if his middle fingers were glued to his palms, Grandma used to say there was nothing he couldn't do with them. He could fix anything, work with tangles of electric wire, even tie flies.
When I was a baby, he used to sit with me out in the kitchen, telling me that I'd have a private rocketship to take my dates up to the moon, and that he would buy my condoms. He died when I was only 10 months old, when he was younger than I am now, so I don't have any memories of him. But I have his name, probably his hair, and possibly his little finger...
...which is perfectly shaped for adjusting the tension of your yarn when knitting.