NetSpeedMonitor - NetSpeedMonitor is a lightweight Network Monitoring Toolbar for your Windows Taskbar
Venmon - Compact size system resources monitoring utility and multi-ping tool for Windows
NetTraffic - Essential network bandwidth monitor.
Taskbar Meters - Incredibly simple meters that live in the Windows 7 task bar.
FreeMeter - Monitor network bandwidth (C#.NET 2k/XP+). Desktop and Systray graph.
Mousotron - Mousotron is a mouse and keyboard activity monitor and keeps statistics of your mileage. It's like an odometer or tripometer for your mouse cursor.