It’s the HD-DVD Processing Key for most movies released so far...
The war on the commercial movie industry rages on...
To spread the numbers became a support act against the major censorship campaign that started at digg.com (where it all started)
(not saying frosty did tho..)
You need this key to decrypt HD-DVDs... Partly to watch them on a linux system, but probably mostly for all the pirates out there.
edit:
censorship is usually a bad thing, so for me it was a perfectly relevant campaign.