Non-Linux FOSS: AutoHotkey
Text expansion and hotkey automation are the sort of things you don't realize you need until you try them. Those of you who ever have played with system settings in order to change the function of a keystroke on you system understand the value of custom hotkeys.
For Windows users, the customization of keystrokes is pretty limited with the system tools. Thankfully, the folks at http://www.autohotkey.com have created not only an incredible tool for creating scripted hotkeys, but they've also included automatic text expansion/replacement for speed boosts on the fly.
Programming the hotkeys and text replacements is pretty straightforward, and the Web site offers plenty of tutorials for making complex scripts for elaborate automation. Even if you just want to do a few simple hotkeys, however, AutoHotkey is a tool you really want to check out. Best of all, it's completely open source, so there's no reason not to go download it today!