Be fair, Pete. You know in February I get to decide what shape the Earth is, because it's my birthday.
In February 2011, I have decided the Earth's surface is a Klein bottle and is therefore unbounded and one-sided. So you can't go through it - you would just see your own feet disappearing into the same hole you are emerging from. Fortunately for the people who keep carping on about infinite luminousity and rotating long sticks, a Klein bottle has zero volume, although below is a site that will sell you a large or small Klein bottle, both of zero volume.
They will even do you a Klein Wooly Hat, or for beer drinkers, a Klein Stein.
http://www.kleinbottle.com/