What is the Psion Siena? It is a PDA that was made in 1996 that has a 16-bit monochrome display with 512k of RAM. It runs on 2 AAA batteries that last about 2 weeks if you use it regularly. So, how did I get this? A friend said he found it in his uncle's basement and since he didn't have a use for it and knew I liked computer stuff, he gave it to me. I had no idea what it was when I got it about 2 years ago, and so I used it for about a week and learned the basics of it. Since then I've gotten it out periodically, it still works for its intended purpose, but there aren't really any modern uses for it other than a prop for a movie set in the 1990s.