I've written a small groovy script to convert a CSV file full of points of interest into a KML file full of Placemarks. I unimaginatively called it csv2kml (with apologies to all the other csv to kml converters called csv2kml). I suppose it's full name is csv2kml.groovy, but that's a bit of a mouthful.
What happened was that I came across Little Chef's homepage and I saw that they had released a CSV file containing the coordinates of their restaurants. From what I can tell, this is a fairly common way of sending around POIs for Garmin GPS units, so hopefully it will work for most CSV POI files out there (though no guarantees).
Hosting for the project is provided by the big G - you can find it here. At the moment, I haven't released any files, but you can get the script from subversion (go to the source tab and then browse the repository - it's in trunk)