In the Interactive Technology Design course (ITD) at IDE students design and prototype tangible interaction concepts. The challenge is to make an interactive product without resorting to traditional solutions such as screens and buttons. This year's subjects were for example an interactive playground for girls (Nelson), a fitness coach for bike training, visual reminder products (i.e., rotary reminder), and interactive portals. There is a ITD YouTube channel providing an overview of the results of the last few years, including my personal favorite from last year: Forelorn's Fortress (see movie above), but Invisiball seems like a cool game too. Or you can go for Heist if you're more of a Mission:Impossible kind of person.