Royal Pingdom has made good use of Google's Maps to illustrate the location of Google Data Centres around the world. Being the world's favourite search engine takes enormous amounts of computing power and therefore Google’s data infrastructure needs to be huge and spread across the world. According to Google’s earnings reports they spent $2.4 billion on their data centres in 2007 alone.
Google is rather coy about how many data centres it uses and where they are located but Royal Pingdom have created some Google Maps based on information published by Data Center Knowledge.
As well as using static maps Royal Pingdom have also put together an interactive Google Map of the data centres at Wayfaring.