vincevincevince - 2:27 am on Jul 5, 2007 (gmt 0)

The answer could well come from the oldest technologies matched with some of our newest innovations. For example, some of the oldest surviving documents are cave paintings and engravings. Fast-forward to today, and etch your documents with ultra-high precision lasers onto diamond slices.

Assuming that we can still read the characters used today, then any future generations for the next few billion years would be able to read the diamond. Really stable things, diamonds!

Sure, you would need OCR to digitise it into whatever your modern system is, but if future generations can't manage OCR then I formally disown them and they deserve to have decayed unreadable archives.