TrayStatus is described as 'Do you have a notebook or keyboard without a NumLock or CapsLock indicator light? Do you have a computer without a hard drive activity light? If so, then TrayStatus is for you'. There are more than 10 alternatives to TrayStatus for Windows. The best alternative is CapsLock Indicator, which is both free and Open Source. Other great apps like TrayStatus are Keyboard LEDs (Free), Keyboard Notifier (Free), KbLeds (Free) and addLEDs (Free).
Keyboard Notifier sits in the system tray and notifies the user as to the state of the Caps, Scroll and Num lock keys. Designed for systems with ill-placed or non-existent hardware notification lights.
Some of the latest keyboard and notebook models no longer have indicators for the status of the Caps Lock, Num Lock and Scroll Lock keys, and some people prefer not to have to look away from their monitors even if their input devices are equipped with these indicators.