As someone who spends a lot of time at the keyboard I find that RSI (Repetitive Strain Injury) is a constant visitor. Working on a laptop, even with a full-sized keyboard I find that the little finger of my left hand is the biggest problem as it spends so much time at the bottom left of the keyboard on the ctrl and shift keys, bent back on itself under my hand.
A fried (thanks Rob) passed me a link to AutoHotKey a utility for scripting the mouse and keyboard and I have found that by remapping the keys on the left of the keyboard this has helped no end. I list my script here for interest, but you will need to find what works for you.