I don’t make these up! TweetPenguin is a site to help you find others that have the same interests via referrals it seems.
To use the service you enter your Twitter username, password and interests (74 character maximum, comma separated, so be prudent and concise). Your first interest is then shown in a public tweet.
NOTE: Pay attention before you fill out your information as above this sign-up area is a list of people. They have check marks next to their names and their interests show on the right. However, by leaving them checked you start following them. This is how the list builds and referrals work. A mini pyramid since the site does not yet offer the ability to search for someone based on common interest.
I found where they starte this is coming, but I am not using it until that part of the site is built. I want to click and find others that share an interest, see their recent 20 tweets or so and then decide to follow them.