Speedtest.net lets you test the speed of your internet connection in relation to a server anywhere in the world. Many Internet Service Providers have teamed up to tell you, the internet user, if your ISP does give you the upstream and downstream speed you pay for. It also tests latency expressed in ping-speed.
Internet speed testing services have been around for many, many years. And so has Speedtest.net. But they have been superior to any other service I know for as long as I know them. I especially appreciate how you can test your speed to a particular location, making it a useful tool for analyzing why sites from one particular region might load slow.
It has been a bit difficult before to select exactly the location I'd want to test to, but now that they have updated the display of their map, this has become extremely easy.
They rock! Do I need to say more?