>Another way to look at it would be going the other way smaller - nanotechnology - check out articles by Eric Drexler on the net. Tracking billions and billons of 'nano machines' produced by molecular production lines might require exabytes to track 'em....
>
>>>Current estimates of numbers of stars in the galaxy are around 200 billion, so around 80Gb per star in the galaxy.
>>
>>Done it again, 3 extra zeroes this time - that should be 80Mb

Coincidentally, I had just come across this site discussing the same issues :

http://www.zyvex.com/nanotech/MITtecRvwSmlWrld/article.html