I actually got Node Runner working this afternoon. The application works fine now, but it took some doing. For the record, I had to manually edit the data in the mysql database it maintains in order to get it to work with hostnames rather than IP addresses. (This was Node Runner version 0.6x, so that might explain some of the clunkyness.)
Other than that, setting up the crontab took a little extra doing ... but that was my fault.
Openacs looks like a good service! I think I can use that for some monitoring as well -- like monitoring the server that I'm running Node Runner on.