There are a lot of awesome data sources out there that are currently being put up for public consumption by small independent teams, one example being DrugCite.com which takes the FDA AERS (Medication Side Effect) data and lets you search by drug name, side effect, ect. then sort it be age and gender.

Ok, I get the purpose here, and it's a nice layout, but how do you plan to monetize this, or do you plan to?

The members of our group all work day jobs doing medical informatics, so we're more or less medical data geeks who identified a hole in the medical informatics field and exploited it. I do it for it fun, although I can't speak for the other guys in the group. I'm the main programmer so I get a certain amount of enjoyment watching our traffic grow. Even though we're not monetizing our traffic (ads, etc.), there is a sense of satisfaction we get knowing we're empowering consumers, providing a research tool for pharma companies, providing actionable data to physicians, and generally taking obscure messy data and making it clean and usable. This project is very satisfying. Right now we're just happy knowing other people find it useful.

I wonder how many of those accounts haven't been accessed in several months or a year. I thought previously twitter was primarily run by a small percentage of power users.

That's true. They have managed boost it in the past two years, but the amount of active users are still only in the region of 100 - 150 million.