vnstat (a console-based network traffic monitor)

vnStat is a network traffic monitor for Linux that keeps a log of daily 
network traffic for the selected interface(s). vnStat isn't a packet 
sniffer. The traffic information is analyzed from the /proc filesystem, 
so vnStat can be used without root permissions. 

This program is open source (GPL) and can be installed in 'single' and 
'root' mode. 

See README.SBo for post-install configuration.