I work in the equities group in an investment bank. Joel's probably right about a lot of wall street jobs but certainly not all of them. I'm not even involved with the most math/CS intensive stuff but I still work on:

- Creating/consuming "real-time" data feeds with thousands of events per second

- Custom pub/sub in-memory databases

- Complex event processing on streaming data

- Homegrown data structure libraries designed for low-latency applications

Honestly, it's a lot more interesting than what I used to do at large public websites. The hours are no worse and when you include the bonus I bring home 2x as much. The cap is also insanely high, even for people who want to stay coding 90% of the time.

Sure, it's nothing like working at a startup. There's lots more meetings, you're a cog in a giant machine and no one outside of the company ever gets to see what you do. I bet working at a small hedge fund/prop shop approaches the best of both worlds.

It gets frustrating when so many otherwise knowledgeable folks write off an entire industry.