[jameswyse]

One thing I love MongoDB for is it's geospatial indexing abilities: http://www.mongodb.org/display/DOCS/Geospatial+Indexing

Was a really nice surprise when I was building a location based web app.

[jsemrau]

That was our use-case as well. And it works fine for this but just in the application layer. We are not using Mongo for data storage (at least we are not trusting it to hold it for long)

[wakaflaka]