Hi there!
I always wanted to make something like this: http://kiwiembedded.com/windsond/
For those of you who dont want to read this (I fully understand), it is a small chip, equipped with GPS and a transceiver, which is launched in the air by a helium balloon. It measures and sends live the wind data to a computer on the ground. When a certain altitude is reached, it detaches from the balloon and tells the computer where to find it. The whole chip (with the above components plus a beeper, baro-sensor, flashlight and battery etc) only weights 12grams (0.42oz). The weight is crucial, since the small heliumballoons cant lift more.
I always thought that it is not possible to get such lightweight components, especially the GPS and the complete radio system. Unfortunately, I cant find such components or suppliers. I'm aware, that using such components can result in me not being able to solder them myself.
Could you help me find the components to realise something like this? Thanks!