

Popular Mac OS emulator system, Open Emu, has added a Game Boy shader and a bunch of CRT shaders, which can be downloaded now.
Open Emu is an multi-platform emulator for Mac OS and more information can be found out about it here.
Below is a sample of how the new filters look:
CRT
Standard view, no filter:

CRT Aperture

CRT Caligari

CRT Dr Venom

CRT Dr Venom (Fast)

CRT Grungy

CRT Lottes Multipass Glow

CRT New Pixie

Gameboy
Without Filter

With Filter:
