Pinout of the Raspberry PI GPIO header -> http://www.raspberrypi.org/archives/384
So it has I2C, serial and SPI. I'm waiting to buy a Raspberry till there is enough online documentation on how to use these pins. I would like to connect an Arduino to the Raspberry for a robot. For a programming noob like me the raspberry is to difficult to program but if there is enough online info/tutorials then maybe it's worth buying. I bought a book to learn Python some time ago, might be useful 