Though it may be fun to see in a few years how sites, and content were displayed I think it would not really be worth it to archive the complete internet. I imagine from 10,000 web sites, only one actually contains fact data, the others just display, categorize or interpret the data differently. Not much of the actual fact data should get lost, thus the data, that is obsolete may. Back in the days, the problem was storage, should not be really the problem these days though.
But to Gullaninas suggestion, having it as a payed service would not fly either. If only 1% would pay for it, you could be more then lucky so again you would have a big hole.