"What do you do?"
I am a researcher and a speech-language pathologist.
"That doesn't sound like a Slashdotty kind of job. What are you doing here?"
I do R&D on augmentative and alternative communication systems. I learn a lot about new hardware and software things here.
You know that computer rig that Stephen Hawking uses to communicate? That's an AAC system. I develop those. And do research on how to make them better and easier to learn.
It's the intersection of linguistics, human-computer interface design, hardware hacking, and the social sciences. It's about as geeky a field as I was able to find that also makes people's lives better in a very real and tangible way.
And I have to say, thank goodness for Dr. Hawking, because if it weren't for him I'd never be able to explain to people what I do for a living.