Is It Down Right Now? - Network & Admin
SmokePing - Smokeping is a tool for measuring latency.
UPDOWNtoday - UPDOWNTODAY allows you to check whether the website is down or not.
Ping Meter Gadget - Customizable, graphical, semi-transparent ping (latency) meter.
Site Down - Site down outage and downtime reports from SiteDown.co
Open Nettest - Open Nettest is a platform for collecting, processing and visualizing data related QoS and QoE.