automounting usb devices

[David Rysdam]

Normally, I plug in USB drives (such as my mp3 player) and it just
automounts. Eventually, after some number of months, it doesn't. I have
absolutely no idea what needs to be restarted. I hate rebooting.

The only things google has told me are:

1) nautilus
2) hal

Restarting the former doesn't fix it, restarting the latter seems
unpossible. 

PREVENT REBOOTING! Help me!