This next game from the TIGSource Procedural Generation Competition is definitely not for people with reactive epilepsy. Utilizing a procedurally painted background that is continually painted in real-time (which is almost a game in of itself), Everyone Loves Active 2 is an arena shooter with very simple mechanics and a visual style all its own. Kill enemies within seconds of each other to get chains, and keep going to rack up a huge score. There's even online leaderboards for those who want to show off their prowess. You can download it off of the TIGSource forums.