There is an interesting feature on VGA, HDMI or DVI ports called DDC. This is a simple communication channel between your screen and your computer that allows the latter to retrieve informations such as resolution and framerate.
Good thing about it, you can use it as a I2C bus (under Linux at least). As I figured it out later, I’m not the first one to do it (of course) and guys at POD-Bot did very similar stuff here. Anyway, having an I2C bus directly on my computer will allow me to connect lots of stuff to it. (more…)