TapTap Hotkey Extender is a tiny super-efficient tray-based utility (under <100k) for keyboard fanatics.
It monitors for certain unusual hotkey combinations not supported by most programs (like doubletap right shift key). When such hotkey combinations are detected, TapTap will simulate a normal hotkey that the user has configured.
In this way, you can configure any of your programs to respond to these extended hotkey events as if they supported it natively.
You might have a program which normally triggers on Alt+Ctrl+F5, but you want to configure it to trigger with a double tap of the right control key. You can use TapTap to detect Right Control Doubletap events, and send a Ctrl+Alt+F5 when it does. In this way, you can control your programs the way you want to, and they never know the difference.
TapTap Hotkey Extender is written in lean and mean C++ and highly optimized for insignificant cpu/memory access. It makes no changes to any system files and is completely safe. Comes with an installer but you can unpack the download manually and run it without installing.