Here are some projects that have been done by mostly ITP students over the past couple of years.
Hardware might not be hard, but it does take time. So remember that a lot of the following projects took at least an entire semester to work on. A few of them actually started as a smaller prototype in Circuit Design and Prototyping.
I'm probably missing some great projects that I can't find, so let me know if there's more I should post!!
Fun presentation on making a DIY cellphone. Not from ITP, but still a good example of using datasheets, modules, and enjoying the process.
Andy Sahlstrom's MIDI Player Piano uses transistor breakouts to autonomously control a piano.
Laura Chen's smile sensor uses electrodes to detect when a user is smiling.
Abhishek Singh and Jingwen Zhu's lumen shoe, has many PCBs to hold neo-pixel leds, and connects to user's phone over BLE. Design and modeling by David Tracy.
Kina Smith's 2015 thesis, Compost Sensor, used custom boards to make a cheap wireless network to help local composting sites.
Pedro Galvao's 2015 thesis, Backslash, used custom boards designed for protesters in the future.
Billy Dang's 2015 thesis, $weat, used custom boards to measure a person's sweat amounts.
Kate Sukpisan's 2015 thesis, Nobacco, used a custom board to detect when users are smoking, and then notify their smartphone.
Aaron Sherwood's Micro, used a custom board to prototype one orb, and he then used a board house to make a few hundred more.
Allison Burtch's 2014 thesis included the Log Jammer, where she used a custom board to make a RF jammer fit inside a wooden log.
My 2014 thesis: How to Make the Internet of Useless Things, used custom boards to make wireless toys.