I thought I saw this when surfing the other day, but can't seem to find it now. I'm looking for a script that will allow me to insert a preset block of text using a keyword, or perhaps a keyword plus a keyboard command. For example, I would type "syl" and it would automatically be replaced by "See you later!"

I am mostly looking for this as a tool to use in gmail, but I can imagine other situations where it might be useful.

Does this exist?