Not every user has the luxury of a Internet flatrate and I personally know a few who are still using time or data related accounts. I experienced this as well when I used my mobile phone to connect to the Internet during a holiday. Every byte counts sometimes and it is always a good idea to monitor the bandwidth that you are using in that time.
Not only because it gives a clue about the bill that you can expect at the end of the month but also to have proof that you did not download more than the amount shown in the logs of the software.
The Cyber Bandwidth Monitor is one application that monitors bandwidth usage and displays daily, weekly, monthly and total stats. Each period is divided into uploads, downloads and a combination of the two to give you exact data that you can work with.

The user has the option to display a system tray icon that is showing a (mini) graph or a smaller window that can be set to be always on top. There is also a ping and traceroute function but I do not think that many users will need that.
Buttons for alerts and exports are also available but the functions have not been implemented yet. They will be most likely added in the coming releases.
Cyber Bandwidth Monitor is using roughly 6 Megabytes of RAM when run in the system tray.
Related posts:
- Network Bandwidth Monitor
- Bitmeter II Bandwidth Meter
- Monitor your traffic
- Limit Upload and Download Bandwidth
- Throttle Bandwidth of Firefox and IE
- Multi-monitor Taskbar
- Readyboost Monitor
- Save Network Bandwidth

I’ve been using NetMeter (http://www.metal-machine.de/readerror/index.php)for a while now. It’s pretty mature, seems to do everything that cyber does except ping/tracert. It can give you a projected usage for the day/week/month and you can export the logs in csv format. It also takes a minimal amount of ram.
I’ve been using the free Bitmeter2 from:
http://codebox.no-ip.net/controller?page=bitmeter2
from speedapps.com?
http://www.download.com/Cyber-Bandwidth-Monitor/3000-2085_4-10780023.html
Please update: this is actually stolen code. The original author has discovered this and has removed the original open source code and transferred it to closed source for the time being.
http://sourceforge.net/forum/forum.php?forum_id=849469
As T said it is stolen code. (From ‘Free Bandwith Monitor) But worse it is… MALWARE! It installs a toolbar and 2 other undocumented processes. Don’t install it. Also check forums.spybot.info/showthread.php?t=44651
Yep! After installing this one you’re in that painful spyware removal mode.
mmm…on mac I use ProteMac meter