An Alexa or Google voice activated assistant (and setting it up for them), so they can watch movies, play music, etc.
3 months of netflix, prime, audiobook membership, etc
Tobii eye-tracker for gaming/mouse movements, foot pedal buttons
Foot dexterity toys, balls, rocks - so they can get better using their feet and toes.
A ebook with voice activation
A big touch screen monitor hooked up to their cellphone / computer so they can do computer stuff with their feet. And screencast/chromecast to a big tv display. So navigate with feet, and big display for easy viewing.
A huge cost-co sized bottle of anti-diarrheal pills.
A stadium pal, or leg strapped urinal device.
Gag gifts
Sign up for you friend to get visited by the mormons or the 7th day adventists (I mean, he has to fill his days doing something, right?)
Cattle scratcher post
fleshlight mounted on a pole