It works pretty well for tasks that are executed infrequently (no need to have a full application deployed), out of band (no need for a rapid response; we'll email you) and for tasks that can consume excessive resources (threatening other apps running on the server).

For us the perfect use case is the production of PDF reports: they aren't run that often; they can be emailed a few minutes later; and when too many of them are run at the same time, they would steal all the RAM on the server.