Keyboards for One Hand?

visibleman asks: "Having recently damaged my right hand to the point where it is unusable for a month and only for light tasks after that I was wondering whether anyone in the community knows of any devices which replace the keyboard but require the use of only one hand. I remember a long time ago seeing in magazines something that had a single button per finger and relied on the user learning key combinations to make up letters but I have not seen this for ages, does anyone know what I am talking about?" Ask Slashdot covered this topic, twice: in this article from 1999 and a followup from 2001. For those readers who find themselves in this same situation, what solutions have you found and what were your experiences, good or bad? Are there any new devices in this vein that deserve mention or are the older solutions still the best?