xLights is a free and open source program that enables you to design, create and play amazing lighting displays through the use of DMX controllers, E1.31 Ethernet controllers and more.
With it you can layout your display visually then assign effects to the various items throughout your sequence. This can be in time to music (with beat-tracking built into xLights) or just however you like. xLights runs on Windows, OSX and Linux.
For more information visit the official website: