This came out of a hackathon[1] and offers a bunch of useful commands:

/uber ride [origin] to [destination] -- Request a ride from [origin] to [destination].

/uber estimate [origin] to [destination] -- Get price and time estimates to drive from [origin] to [destination].

/uber status -- See the status of the last ride you requested on Slack.

/uber share -- Get a link to share your ride's progress.

/uber cancel -- Cancel the last ride you requested on Slack.

/uber help -- Get a list of available commands.

[1] https://devblog.uber.com/uber-slack-a-weekend-a-story-of-ope...