We have a couple of students working on bringing up the hardware in the Pimoroni Trilobot kit on QNX, but adding some ML to the camera for some kind of autonomous steering perhaps. It will be the perfect blend of intensive processing (camera+ML) with hardware control (short high-priority interrupts). (P.S. hope to open-source this when they are done, along with some blog posts or tutorials -- stay tuned.)

Separately, I think making a GPS-synced weather station would be a fun project. QNX is often used when tight timing is needed for telemetry, so using it to collect weather (and other) data, including from pulsing hardware like an anemometer, and then publishing it to an online service would be a lot of fun.

If software-only is more your style, there may or may not be someone in the office next to me porting some classic games right now! =)