I received my Raspberry Pi Zero earlier this week
While holding it, I noticed one of the USB hubs I had, had the same form factor as this new Pi. So I combined the two into a as small as possible package.
The Pi is powered from the USB hub and the USB OTG port is connected to the hub, providing 4 ports for connectivity allowing to connect wifi/keyboard/mouse/bluetooth/...
All connection details for the wiring etc ... are available in a complete blog post on my website should you want to recreate this build: Raspberry Pi Zero – USB Hub Mod | Frederick Vandenbosch