[smsm42]

Another format would actually be a problem - finding a format that would be readable in 10K years is a huge challenge, since all current languages, semantic systems, etc. may be completely forgotten by then. Check out this one:

http://en.wikipedia.org/wiki/Human_Interference_Task_Force

about trying to solve how to say "dangerous radiation" so people in distant future would understand. Not trivial task at all.

[Retric]

Persionaly, I suspect a scale model of a DNA strand + it's encoding would be a strong enough hint for any society capable of using that data to build a life form. As up you only need 4 symbols for the encoding. Then just repeat that at ever smaller scales.

The real issue is you need to encode a lot of data in a stable form for a long time for cheap enough someone would pay for it. Pluss, the cost of actually sequencing 10K+ plants * a few examples so you have some genetic diversity.