Create a searchable distributed bittorrent style network on which people share whatever information they want to make public.
So basically Facebook but even slower because it has to fetch every little bit of information from unreliable home servers?
We tried that before, and it sucked so much we welcomed flash with open arms afterwards.
Windows Media Player plugin, Quicktime plugin, Real Media plugin, and I have a feeling I'm missing at least one other also-ran.
Machines that have broken down will work perfectly when the repairman arrives.