Launching your own short-term space satellite is now pretty easy - you just need a weather balloon and a hardy mobile camera for documentation. Here's a terrific set of videos showing the successful flights of spacecraft created by ordinary people.
Top photo by Alex Baker, from a composite he made of the "thin blue line (the Earth from space)."
In late 2007, Alexei Karpenko launched a spacecraft using a high-altitude balloon to lift a camera, GPS, and communications equipment to 30 km above Earth. He reports:
High altitude ballooning is an emerging hobby, since price of GPS and communications equipment has gotten quite low. It is an excellent hobby for people fascinated by space flight and telerobotics and has many learning aspects - from systems design to electronics design to software engineering. There is also an exciting risk factor, namely, that you could lose your precious electronics if something malfunctions. In this project, many of my interest and knowledge areas came together. Also, I have verified that the Earth is indeed round and that space is black.
Find out how he did it on his website.
MIT students popularized the craze for cameras in space with this incredible series of pictures from a camera and balloon they sent up for $150. Find out more about these students' Project Icarus on their website.
Late in 2010, a bunch of Google engineers sent some Android phones and tiny green corporate mascots into space. If you find it irritating to watch a video featuring a corporate mascot, you'll enjoy the ending, when the tiny green doll whirls into space where it will surely perish in our atmosphere. Mwhahaha!
A father and son team in New York City launched a balloon with a camera, parachute, and GPS device so they could locate it when it landed. This video is a great document of their adventure launching a space probe together, with incredible footage above the Earth.
In the UK, Alex Baker and Chris Rose did this great video documenting the creation of a DiY space probe. Bonus points for all the stop-motion animation as they built it. They also explain how they created the probe on their YouTube page.
Just in case you were starting to feel really badass about how you're going to make a satellite that flies up into space, consider the fact that in 1960, Joseph Kittinger sent himself 30 km above Earth with an atmosphere balloon . . . and then jumped out. Yes, he did a 30 km freefall, which ended with a nice soft parachute landing. It was the highest freefall ever, and he filmed it.