ScummVM - Game engine recreation of SCUMM made by LucasArts.
Spark Mail - Spark helps you take your inbox under control. Instantly see what’s important and quickly clean up the rest. Spark for Teams allows you to create, discuss, and share email with your colleagues
DOSBox - DOSBox is a DOS-emulator that uses the SDL-library.
Newton Mail - Newton is a fully featured mail client available for Android, iOS, macOS and Windows.
RetroArch - RetroArch is a frontend for emulators, game engines and media players.
Aqua Mail - Android Mail Client.