They aren't the first to do something like this.
Here's a very similar project made in 2007:
Here's a very similar project made in 2007:
As well as taking photos, they've taken passengers: http://www.srcf.ucam.org/~cuspaceflight/images/nova9selected...
Q:How much did it cost? A:The system that is presented is a little over-engineered for historical reasons as well as for future expansion and test purposes. It's possible to build a system for $500 with just a cellphone link and a microcontroller, but make sure that coverage is good where you intend to launch and use a good cellphone antenna.
Edit: Take the camera for instance. The MIT students used a Canon PowerShot A470 (they bought it used from ebay) which costs $120 new and is 7 mega pixels. This guy used a similar camera (Canon PowerShot A70) which was only 3.1 mega pixels and costed $350 when it came out.