MIDI controllers come in all shapes and sizes, from grid-based pads to traditional-style keyboards, touch screen tablets to rubberised 3D expressive formats. There's always space for the more unusual and unique music controllers too.
In the hands-on demo video below you'll meet Playtron, "an electronic device that lets you turn any object into a musical instrument. Touch anything conductive - water, fruit or human body and control your computer, smartphone or your favourite synthesizer via universal USB MIDI protocol." In this instance there's even three pineapples turned into a MIDI controller.
Next up, is Touch Me, "a device that turns human touch into music. When the surface area or intensity of skin contact between two or more people changes Touch Me modifies sound output according to selected scale and tone parameters."
There's also a color pallete based controller on show which is used as a rhythmic sequencer!
Of course, there are other options for turning literally anything into a musical instrument... Dada Machines Automat is absolutely amazing and deserves everybody's attention. OpenDeck Shantea makes it easy to create your own MIDI controller from scratch. Pulse Controller can transform any tabletop into drum pads. And if you really want to go the DIY route, this tutorial on how to build your own DIY MIDI controller using Teensy is a must-read.
Learn everything you need to know about MIDI (and have a chuckle along the way): https://ask.audio/academy?nleloc=course/1198/midi-demystified