Artisans Cooperative: Etsy-ish
Brave: Tools for overdose prevention
Candlestick Courier Collective: Bike couriers, mainly food delivery (SF)
Comradery: Patronage
Fairmondo: German eBay alternative
Free Food: Delivery service
La'zooz: Ride sharing based on a "proof of movement"-based cryptocurrency
Namma Yatri: Taxi service launched by Autorickshaw Drivers Union in India (unclear on technical details) (see also Rook)
Radish: Food delivery in Montreal
Pizzeria Du's Roger Yang is organizing a delivery coop in Toronto
Up & Go: Cleaning services in NYC
Fromto: Food delivery in Vancouver (defunct)
Good introductory essay by Trebor Scholz
A Common Platform: Political economy of platforms and a guide to democratic reforms (UK)