I'm a software developer, so I thought RSI is not a big problem for me. After all I don't type all day long. Eye strain, yes. But not RSI.
Then I've installed WorkPause (reminder app) which also counts the number of mouse clicks and key presses you make during the day.
My numbers are: more than 14000 key presses and more than 6000 mouse clicks for a typical 8-hour working day. And that without the computer usage at home. That's not a small number; definitely pay attention to ergonomics.