Anybody working with a computer probably spends a third to half of his time (when not a lot more) typing on a keyboard. Keyboards are mechanical devices (if yours isn’t, then please do change it now!)
Mechanical devices are not eternal, and the more you use them, the worse they function, unlike brains for instance, which aren’t eternal neither, but usually do work a lot better if you use them often.
A good keyword costs less than $100, a great one usually less than $150 ( no, I did not consider the $2000 Optimus Maximus ).
The feeling and comfort of typing on a brand new keyboard are so enjoyable, that nobody should use one older than 12 months. Ok, if you work on a laptop you can keep it two years, as you probably use it only half the time anyway… using a real keyboard when at home, right?
To celebrate my new job as an Happiness Engineer at Automattic’s, I replaced my two iMacs with a brand new MacBook Pro.
After working exclusively on Apple laptops since 1994, one year ago I switched to the iMac. To two iMacs exactly (27″, Core i7, 8GB Ram and 1TB HDD each), one at home and one at my office.
I kept both synchronized through me.com and everything worked quite well as long as, when on the move, an iPad was enough to check my emails.
Now, things have changed, and when I travel I need a real laptop again. I went to Vienna to meet my teammates for a week with a MacBook Air, and once back it was obvious to me that this wasn’t a good solution.