I mentioned the other day the deployment of three small cubesat spacecraft (10 cm x 10 cm x 10cm) from the International Space Station. They were ejected with a special device attached to the Japanese Kibo module. Below is a great photo of the deployment: Cubesats Released From Space Station – NASA
See the NanoRacks website for information on how to get your cubesat into orbit via the ISS. See also the article : Right This Way to the Space Station – Air & Space Magazine.