Here's an interesting space-saving idea that just popped into our mailbox. The Murphy Gym take the murphy bed concept and applies it to a home training system which allows for up to 200 exercises, and then easily hide it away behind closed doors when not in use... The Murphy Gym folds up into space less than 6" thick when not in use, with an optional Digital Training Display for training guidance/feedback, but is unfortunately priced in a range mostly out of reach to those who would most benefit from the small space-friendly design ($3495+ installation and custom cabinetry work).
Looks like we're not ditching our gym membership any time soon, with our dumbbells and chin-up bar being effective for fitness and easy to store away (though my girlfriend sometimes complains when I hide them under the coffee table, resulting in a sore toe). But we like the idea of an adjustable, multi-movement gym system that hides away easily, so hopefully Super Fitness Canada will look to offer a smaller and more affordable version soon.