How to tear down shared, infinite Observables with a delay after the last subscriber unsubscribed

I thought this was an interesting problem and seemed a useful operator to have so I made Transformers.delayFinalUnsubscribe in rxjava-extras:

observable
  .publish()
  .refCount()
  .compose(Transformers
      .delayFinalUnsubscribe(1, TimeUnit.MINUTES));

It's available in rxjava-extras from 0.7.9.1 on Maven Central. Give it a spin if you like and see if there are any issues.