Propeller and TI calculators (youtube)

mpark

This video is primarily about TI calculators and their data link protocol, but at around 4:50 there's a Propeller-powered printer and later a keyboard interface.

https://youtube.com/watch?v=W_mZ7smIz3U

(Not my video, btw!)

AwesomeCronk

I literally saw that Friday! Fun video!

Genetix

I stumbled upon this gem a while back but I haven't had a chance to play with it.
https://forums.parallax.com/discussion/95591/ti-92-calculator-low-level-driver-checking-interest