Best to buy the kit from them as it will come with everything including the software and driver already on an SD card.
May put one together to play with around the house. Some of the money also supports TOR.
https://learn.adafruit.com/onion-pi/overview
Who is this good for?
If you want to browse anonymously on a netbook, tablet, phone, or other mobile or console device that cannot run Tor and does not have an Ethernet connection. If you do not want to or cannot install Tor on your work laptop or loan computer. If you have a guest or friend who wants to use Tor but doesn't have the ability or time to run Tor on their computer, this gift will make the first step much easier.
What is Tor?
Tor is an onion routing service - every internet packet goes through 3 layers of relays before going to your destination. This makes it much harder for the server you are accessing (or anyone snooping on your Internet use) to figure out who you are and where you are coming from. It is an excellent way to allow people who are blocked from accessing websites to get around those restritions.
