One that has been great for me is just speeding up the mouse. It takes like 20 minutes to get used to and saves so much time in the long run.<p>I thought about a Dvorak keyboard like Matt Mullenweg, but I think it would be a much longer learning curve.
Not necessarily increasing work speed, but saving your hand and wrist in the long run is the vertical mouse from Evoluent. Really helped my hand. Also multiple customizable buttons for shortcuts. Worth the money in my opinion.
<a href="https://evoluent.com/" rel="nofollow">https://evoluent.com/</a>
Depending on the type of work that you do, it might be better to eliminate the mouse all together. For me, moving most of my work into the terminal, using VIM as my editor, etc. has improved my output pretty dramatically, though there was a pretty good learning curve and ramp-up time for sure.