FlashPaste

FlashPaste is a completely free utility that can save you a lot of time if you have to enter repetitive text such as passwords, usernames, set phrases, headers, etc.

It can be very useful for writing emails where you have to repeat parts of the body of the text.

It works really simply. You just configure a hotkey in the program, and when you press it a pop-up menu shows all the default expressions you previously set. You can choose one and enter it where you wish, including text editors, forms, letters, etc.