I had a Psion Series 5 in my high school days -- also something I saved my shekels for. The thing was basically the closest you could get to a DOS computer in y

I had a Psion Series 5 in my high school days -- also something I saved my shekels for. The thing was basically the closest you could get to a DOS computer in your pocket with an amazing UI and full on device programmability. The thing had a full keyboard (!) and word processor which I even used to type out whole essays on. The little computer was a work of engineering genius -- even ran for a month on one pair of AA batteries. To this day, I still have yet to find anything that comes close to that same reliability, stability, or feature standard.