Redis does a lot more than just act as a key-value store. There are numerous instructions for sorting, filtering, and manipulating data. There are message queues, sets, publish/subscribe channels, and even a built in Lua interpreter to run scripts.
If you are looking into using it for anything, it's worth reading the full documentation to find out all it can do. I'm working on a project which uses it, and I'm not aware of anything else that is similar.
Biting the hand that feeds IT
