A flying piano and a smell-maker are just some of the unusual devices on display in Paris that are attracting big crowds.
The "Roman-soldier-multiplier" has proven to be an instant hit
Le Grand Repertoire (the Big Repository) exhibition showcases some 100 machines that have been used in theatres and shows.
Visitors are being sprayed with foam and water, and encouraged to try their skills in operating some devices.
The exhibition is part of the annual Summer Neighbourhood festival in Paris.
Among one of the most popular gadgets is the so-called "Roman-soldier-multiplier" - a machine that allows one person to move a whole row of life-sized Roman legionnaires.
Those who have dreamed of becoming a drummer also have a chance to show off - but suspended in a big, rotating "drumming" wheel.
The exhibition is being held in the glass dome of the Grand Palais, which was built for the 1900 World Expo.