The Wikipedia site is offline this morning and displaying a message saying the site cannot reach its database server. The user-maintained encyclopedia is one of the Internet's busiest sites, despite operating on a non-profit budget and running on several hundred servers. The downtime is not a local event, as seen in Netcraft's monitoring. UPDATE: Looks like the site is back as of 10 a.m. Eastern time.
The Wikipedia site is powered by about 350 servers, most of which are housed in data center in Tampa, Fla. It also has about 50 servers in Amsterdam at a data center operated by EvoSwitch and the AMS-IX peering exchange.