This PCB fits neatly on top of a Beagle Bone, without getting in the way of the Ethernet jack, and provides a breakout to both 46 pin headers - with individual numbering to keep them straight. It also has strips to access the 5V and 3V power supplies as well as two SMT breakouts, one for SOIC-8's and one for SOT-23's.
Kit comes with a double-sided FR4 PCB and 3 sticks of header. You'll need to place the header into the Beagle Bone and then solder the Proto Cape PCB in place, but its very easy and should take only 10 minutes max even for beginners. Beagle Bone is not included.