Turo for sharing cars. It’s car rentals but weird since you’re borrowing other people’s cars.

Kyte is in a similar vein for on demand cars via app, but it functions similar to a traditional car rental in every other way. Though they’re a baby company so they might not be a good Uber comparison yet.
My personal experience has been pretty good and the prices are very competitive, but we’ll see how they survive when the VC money runs out.