Network List Service
Windows Vista Service Details
Maintains list of network connections. With this disabled the tray icon won't be able to tell if you are connected but you can still connect just fine.
Identifies the networks to which the computer has connected, collects and stores properties for these networks, and notifies applications when these properties change.
Consequences of Stopping:
All services listed in 'Required For' will be unable to function
SL UI Notification Service