Ubuntu - gnome panels hanging randomly after using "Connect to Server" (gvfs)??
For ages I put up with random hangs and where some or all of my panels would stop responding, and completely rebooting was the only solution (killall gnome-panels wouldn't unfreeze things either; all the hung panels disappear, but then nothing comes back in their place)...
I knew it had something to do with connecting to other computers by using gnome's "Connect to Server" feature, and since the problem only happened intermittently and listless googling didn't turn up anything I just lived with it.
I had a separate issue where after a certain amount of inactivity (maybe half an hour??) my SSH sessions would stop responding and I'd need to log in again. This is similar to what happens with FTP sessions, so it wasn't surprising, just a bit annoying.
Eventually I put two and two together and realised that much of what I was doing with nautilus/gnome's GUI used SSH behind the scenes, so the two things are probably related. The SSH session that gnome uses is timing out and hanging the panels which stupidly assume that the session is still open.
As with most bug fixing, once you know what the problem actually is the solution is easy.
Add this line to the end of /etc/ssh/ssh_config
There seems to be an /etc/ssh/sshd_config file also, which you don't need to mess with.