Process Explorer v14.11: Process Explorer v14.11 includes the ability to configure network and disk activity icons in the tray.
http://blogs.technet.com/b/sysinternals/archive/2011/05/03/updates-zoomit-v4-2-process-explorer-v14-11-procdump-v3-04-and-mark-live-zero-day-malware-cleaning-with-the-sysinternals-tools.aspx