Check out the Ethoscopes platform!
Ethoscopes enable high-throughput analysis of behavior in Drosophila and other animals for <$100. The system is capable of real-time video tracking, is based on raspberry pi, and even has its own R package for data analysis. All software and build specifications are available at http://lab.gilest.ro/ethoscope.
This research tool was created by your colleagues. Please acknowledge the Principal Investigator, cite the article in which the tool was described, and include an RRID in the Materials and Methods of your future publications. Project portal RRID:SCR_021426; Software RRID:SCR_021507