My family and I recently visited an exhibition at Manchester Art Gallery, 'Recorders' by Rafael Lozano-Hemmer , Mexican/Canadian Electronic Artist.
The works in Recorders actively encourage people to interact with the pieces, they see, hear and feel the actions of people around them.
My favourite piece involved 100 light bulbs activated by a sensor which involved holding onto 2 metal bars, which flashed a large light bulb above my head which then flashed to the exact rhythm of my heartbeat.
Other pieces included a long table where at one end you placed an object that went under a scanner about 10inches wide removed at the other side ,but left a copy of itself on the conveyor like table, to be added to by other peoples belongings, and a finger scanner that my son loved where you placed your finger tip into a small hole and your (dirty) finger nail (thanks son) was on view about 1ft high for everyone to see...x