I get a lot of strange hypothetical science questions in my email. People get in debates with their friends - stuff like "what would happen if someone threw a baseball at nearly the speed of light?" or "how many velociraptors would it take to kill <fictional creature>" - and for whatever reason, they decide to email me about it. Puzzling over these questions is a lot of fun, and so I've decided to set up a blog to collect and try to answer them.
You can find it at what-if.xkcd.com. I'll put up a new question and answer every Tuesday. To start things off, I've got two entries disucssing questions I've received-one about relativistic baseball and one about guessing on the SAT.