Here is something I haven’t seen before: Sightseeing site Googletouring now lets you upload existing KML or KMZ files into a Google Map, in case you have no Google Earth application handy (or use a Mac, say).
I tried it with a piece of KML I prepared earlier, a structured KML file containing the locations of all Swedish university campuses, and found that it displayed well. It doesn’t do network links, (that’d be asking too much) and there are some minor cosmetic glitches still being worked on, but it’s already a handy tool to have around.