Everything goes in cycles, man. I mean, like, it used to be that all controls were things you touched, like keys on a keyboard. Then we got heavily into virtual controls, like “buttons” on a screen. Now somebody has reminded us that there’s a real world out there, man, with tangible stuff that can do stuff. But it’s better this time around! Tangible interfaces can take any object — a block, a salt shaker, whatever — and tag it so the interface responds to its location, rotation, or color. Tangible interfaces could benefit people with physical, sensory or cognitive access issues, but it depends on how they’re built — they may impose new barriers themselves if there’s no alternative. Some days, you just can’t say “redundancy” too many times.
Trackmate, a prototype, is a great example of a flexible tangible interface, suitable for almost any type of application. Inexpensive, too: all open source, with hardware costs under $100. It’s easy to get started, but if you want to do something off-road, there’ll be heavy hacking ahead. A growing user community may be able to help.