I'd love to see a real-world map/reduce example that wasn't wordcount.
"This repository contains a set of example map-reduces using Hadoop.
Specifically, there are examples for:
* Pagerank
* Canopy-clustering "
more examples like k-means here: http://delicious.com/pskomoroch/hadoop+codeWell you can't see it, but yahoo use hadoop for their indexes. So if you use yahoo search, there you go ;)