Circuit bench - 100 shields for arduino

Fun Projects for the Experimenter - volume 2

4093 IC - Circuit Sourcebook for the Makers

Electronic Projects from the Next Dimension: Paranormal Experiments for Hobbyists

Mechatronics for the Evil Genius: 25 Build-it-Yourself Projects

Robotics, Mechatronics, and Artificial Intelligence: Experimental Circuit Blocks for Designers

Pirate Radio and Video: Experimental Transmitter Projects