(Sir) Robolot is your faithful async knight - well as faithful as he can be. Think example.com but for specific web requests.
To make robolot return a delayed response:
# 1 second later $ http://robolot.herokuapp.com/sleep/1 # 10 seconds later $ http://robolot.herokuapp.com/sleep/10
Simply fork and push to the heroku cedar stack
Just pull request :)