In a default Ubuntu install (QGIS 1.8.0) no document icon is associated with the mimetype 'application/x-qgis-project'. As a consequence every saved QGIS document is interpreted by the OS as being a text or xml document and the icon displayed gives no indication it has anything to do with QGIS.
I've googled around and can't find anything; I could make an icon set myself but wanted to see if I'm just missing something before doing it..

