There are plenty of useful things you can do with Ruby and a bunch of servers. This talk isn't about useful things. This talk will show off asinine, amusing, and useless things you can do with Ruby and access to cloud computing.
Sentiment analysis based on emoji? Why not? Hacky performance testing frameworks? Definitely! Multiplayer infinite battleship? Maybe? The world's most inefficient logic puzzle solver? Awesome!
If you are interested in having some fun and laughing at reasonable code for unreasonable problems this talk is for you.