When you safely remove the device in Windows XP it powers the device off - in case of a flash drive its led was switched off and in case of a portable hard drive it was spun down. But Microsoft changed this behavior in Vista and it still exists in Win 7: after you stop the device on these OSes the hard drive continue spinning and flash drive continue lighting. All modern hard drives park their heads automatically when you unplug them so in theory this behavior shouldn't lead to data losses or drive damages. But in practice external hard drive usually sounds strangely when you unplug it on run and this makes a hard drive owner being a bit nervous when he hears that.

USB Safely Remove allows to switch the system behavior on Windows Vista and above to power off USB ports on stopping. This feature is recommended if you have external hard drives since their disconnection in this case will be more safe.

In order to enable this feature just go to the program options and check "Power off the device after device stopping option". Then restart the computer so that this option became active.