The Bussard fusion design, also known as inertial electrostatic confinement or Polywell fusion, has completed the WB7 test which was a replication of the promising WB6 test which was showing a breakthrough in low-cost fusion power.
This is a much simpler design and way cheaper than the direction most other fusion experimentation is going i.e. Tokamak or laser fusion. In fact several high school students have built fusors as science projects. While none of them are over unity (they don't produce more energy than they take in) they are not huge and complicated. http://cosmiclog.msnbc.msn.com/archive/2008/08/28/1301440.aspx
An interesting read by one of the experimenters is available,
Tom Ligon's updated report on "The World's Simplest Fusion Reactor":http://fusor.net/files/EMC2_FusionToPost.pdf