I realize Hudson was not designed as a queue service per se - and that there are other projects like RabbitMQ, ZeroMQ, etc.
We were recently in a situation where we needed to set up a windows executable as a web service with queuing. Because of the platform, time constraints, and my familiarity with Hudson I said : "Hudson can do that" - we trigger a little perl script that runs the executable, and then hits a callback URL. It's been great. We get a nice record of jobs processed. If we needed to scale up we could add slave machines, and the queuing works perfectly.
I have not seen any discussions on using Hudson as a queue service, so I'm looking for reason not to do it for future projects.