The WAN/Network Simulator
WANulator is designed to provide simple to use network simulation for testing and developing purposes. Booting the live CD allows you to turn any PC into a simulator. The GUI interface provides easy configuration of simulation functions like e.g. bandwidth, delay, jitter packet loss and many more. You want to know the user experience of your web/online service used from a modem connection in China? Within a few minutes setup-time you can simulate the conditions with WANulator.
Want to give it a try?