This one doesn't make much sense (since when are micros too big?), but it's cute...

83x58mm when folded, 138mm motor-to-motor (diagonally) when unfolded. So no, its not very micro, I know. And it's one heavy micro, don't expect to do any acro with it. I designed it mostly because I had an idea and I like to draw stuff ;)

The Quanum micro camera/vtx combo from HobbyKing fits perfectly and the camera angle is adjustable between 0 and 30 degrees. The arms have slots for clean wiring and to prevent accidental cutting of motor wires when folding the arms.

I'm running mine with the following hardware:

• Beef's Brushed Board (flashed with Betaflight)
  https://www.fpvheadquarters.com/beef-s-brushed-board.html

• 8.5mm (outer diameter) brushed motors
  https://www.fpvheadquarters.com/angry-beez-8mm-brushed-motor-set.html
  http://www.banggood.com/Chaoli-CL-820-8_5x20mm-Coreless-Motor-for-90mm-150mm-DIY-Micro-FPV-RC-Quadcopter-Frame-p-1054803.html

• Parrot Rolling Spider propellers
  http://www.ebay.com/itm/4x-Propellers-Props-Replacement-Blade-for-Parrot-Mini-Drones-Rolling-Spider-New-/

• Fissel micro frsky rx (only if you have a FrSky compatible transmitter e.g Taranis)
  https://www.fpvheadquarters.com/microfrx-receiver.html

• 750 mah 1S Lipo (a bit too big though)
  http://www.hobbyking.com/hobbyking/store/__41271__Turnigy_nano_tech_750mAh_1S_35_70C_Lipo_Pack_Walkera_V120D02S_QR_Infra_X_QR_W100S_.html

• Micro camera/vtx combo
  http://www.hobbyking.com/hobbyking/store/__89777__Quanum_ELITE_TX_CAMERA_COMBO_Micro_Cam_VTX_25mW_40CH_5_8GHz_NTSC_.html
  http://www.banggood.com/Eachine-MC01-AIO-5_8G-40CH-25MW-VTX-600TVL-13-Cmos-FPV-Camera-p-1065228.html

If you use a Beef's Brushed Board you'll also need an FTDI adapter to communicate with the board
http://www.ebay.com/sch/i.html?_from=R40&_trksid=p2050601.m570.l1313.TR0.TRC0.H0.Xusb+ftdi.TRS0&_nkw=usb+ftdi&_sacat=0

I used the setup above mainly because I already had all the necessary parts at home, there are (most likely) better/cheaper parts out there if you google. There are also a bunch of links in the comments to alternate hardware

Here's a good page to get you started with hardware similar to the one listed above
https://oscarliang.com/fpv-micro-quad-beef-board/

UPDATE 160709:
Added new arms with slits for the motors (as shown in the pictures). Uploaded the wrong version previously, sorry

UPDATE 160716:
Added new, thicker arms for you guys who prints in PLA. These should hold up better in a crash. Also, user unclecracker made a remix of the arms to fit 7mm motors: http://www.thingiverse.com/thing:1675767

UPDATE 170209
Here's a nice camera mount for the Eachine TX03 (and probably other AiOs as well) by murrayp0473
http://www.thingiverse.com/thing:2094946