I felt silly signing up for thissince I don't have too many tampons I need to carry around with me. But you are also entered into a drawing to win a new Toyota Prius as well, which is what got me hooked. I'm currently driving a truck that I'm fairly certain accounts for 14.3% of all carbon emissions made by mankind every year. It's also a certifiable death trap once it tops 45 mph. If you ever see a story on CNN about a wreck caused by a truck vibrating itself to pieces, that's me!
[thanks to Heidi for sending this in!]