After complete several rounds of quadcopter assembly [ trying out various frames and motors ], I have listed some accessories and connectors which I personally found useful and will recommend them to be in your inventory if you are building your own quad/hex/octo copter.

http://flight.farbird.com/2014/03/essential-accessories-for-diy.html

They are listed at the url above

Discovered a method to provide an alternative 3.3V for powering the onboard Baro, Accelerometer, Compass when the built in 3.3V regulator TPS79133 fails.

I documented the details and equipment required here

http://flight.farbird.com/2014/02/repair-blown-33v-regulator-on-ardupilot.html

No solder method to provide alternative 3.3V source to the onboard sensors.