Whoa! Is that really a fully functional Super Nintendo controller attached to the Dell Streak through its PDMI port? Why, yes. Yes it is.
Streak user 0TheRain0 modded his SNES controller using a spare Streak connector (which has been sacrified in the name of hacking before) and a Teensy USB Microcontroller board. The Streak recognizes the gamepad as a USB keyboard (it supports OTG, remember?), which is how it's able to navigate standard system menus, and is said to work with all the emulators available in the Market with no additional configuration.
Don't believe it's real? See it in action below. Better yet, check it out in person by doing it yourself (tutorial here – thanks, Jonathan-Streaker).