MapReduce

If you ever wonder how Google returns such blazing fast results (or how to search through billions of pages in under 0.5 seconds), then read a little about MapReduce:

• MapReduce - Wikipedia
• MapReduce: Simplified Data Processing on Large Clusters - Original paper
• Google's MapReduce Programming Model - Revisited - Haskell examples
• mapreduce in ruby
• mapreduce lectures - on video.google.com