According to the licensing arrangement granted by MIT, the Handy Board design—including the printed circuit board artwork, schematics, and software system—may be licensed for any purpose at no charge to the end user. This means that you may print up your own Handy Board PC boards, use them for your own purposes (educational, research, hobby, or industrial) without having to pay royalties to MIT.
Please note that MIT retains the copyright to all Handy Board intellectual property. The Handy Board is emphatically NOT in the public domain; rather, it is owned by MIT but licensable at zero cost.
According to the license, copyright information (copyright © 1995–97 MIT Media Laboratory) and authorship attribution (by Fred G. Martin) must be kept intact when the work is advertised, redistributed, or otherwise promoted.