Turaco CL is a tool for extracting PNM image files out of arcade game ROMs. It also can regenerate arcade game ROMs from PNM image files. Once the image files have been extracted, you can edit them in your favorite paint program. They can then be encoded back into game ROMs to be played in an emulator or real arcade hardware.
asq is a simple frontend for MAME/emulator cabinets. It runs in a terminal window using curses, and pops up an optional screenshot window. It uses MAME/emulator keybindings so you can control your MAME cabinet using just your MAME controls. (In fact, this is where the name comes from--player 2 buttons 1, 2, and 3 are "asq".) It can also remap your games to use MAME keys. asq is meant for people who don't want to use a keyboard and have lots of games to manage.
A220 Mission 1 is an arcade game written as a Java Midlet for cellphones. It lets you fly through mountains and cave systems, eliminating multiple enemies before finally destroying the Pirate Base. You pick up weapons, shields, and fuel powerups along the way. There are multiple levels, terrains, and enemies.