Software that lasts 200 years

Interesting piece about the throw-away-thinking of the current software. Where paper is readable as far as over a thousand years, current electronical documents tend to be unreadable after as much as 20 or 25 years [think Word Perfect and older word processors]. Of course there are filters for the most popular ones, but compare that to the paper documents your [great]parents made and our electronical systems pale considerably. It's the reason why I tend to use as much .txt ascii documents as possible - it's great readability is demonstrated by the RFC documents; even the original RFC 1 is readable in almost *any* text reader you can imagine. So this guy makes a good point at trying to design software that lasts longer than 3 years [think current office implementations]: more like 200 years.