Even if you have no use for storm, I'd strongly suggest you check out the wiki on github and browse the source code. It is IMO the nicest, cleanest, most exciting OSS project out there.
The code itself is nice and clean, take a look yourself (chosen randomly) [1][2]
It's exciting because if you've ever done any real time processing of data streams at scale or even been daunted by the idea of it, and you read the wiki, it's clear storm is an exciting option. It does for Big Data Streams what Hadoop did for Big Data.
Kafka is interesting, but they don't really address similar use cases. They are more complimentary and in fact storm has a spout implementation for kafka[3].
They are more complimentary and in fact storm has a spout implementation for kafka
I would add to this that a lot of Storm users (myself included) use Storm together with Kafka - that is, Kafka is used to get data into (and possibly out of) Storm while Storm does the actual processing. Kafka is more along the lines of Kestrel and RabbitMQ.
https://github.com/nathanmarz/storm