Is It Down Right Now? - Network & Admin
NetSpeedMonitor - NetSpeedMonitor is a lightweight Network Monitoring Toolbar for your Windows Taskbar
Site Down - Site down outage and downtime reports from SiteDown.co
NetTraffic - Essential network bandwidth monitor.
Is it Down? - Is it down can check if a website is down or is it just your PC that can not access it.
FreeMeter - Monitor network bandwidth (C#.NET 2k/XP+). Desktop and Systray graph.