gdk-pixbuf supports the format for windows animated cursors, shared-mime-info doesn't know it. It would be good to add it, since I plan to make gdk-pixbuf use gio (and thus shared-mime-info, indirectly) for sniffing.

Here is the relevant excerpt from the pixbuf loader:

        static GdkPixbufModulePattern signature[] = {
                { "RIFF    ACON", "    xxxx    ", 100 },
                { NULL, NULL, 0 }
        };
        static gchar * mime_types[] = {
                "application/x-navi-animation",
                NULL
        };
        static gchar * extensions[] = {
                "ani",
                NULL
        };

        info->name = "ani";