The internet will be shut down for cleaning for twenty-four hours from March 31 until April 2. This cleaning is necessary to clear out the "electronic flotsam and jetsam" that have accumulated in the network. Dead email and inactive ftp, www, and gopher sites will be purged. The cleaning would be done by "five very powerful Japanese-built multi-lingual Internet-crawling robots (Toshiba ML-2274) situated around the world."
Here is the announcement. Don't forget to cover up your cable modems, DSL routers, and other high speed connections. If you don't the dirt will blow out of them and get all over everything. No telling what kind of dirt could be blown out. If you use a router between your private network and the internet, make sure that you put plastic plugs in the open ethernet connectors so that stuff doesn't drip out and get on the floor (good tip from daval)..