MacLampsX 2.0 (Free) PowerPC 10.4/10.5 (Tiger/Leopard).
I just came across an app that lets you play around on your Desktop! MacLampsX brings light to your Desktop, it allows you to decorate for Christmas and many other holidays. It has a small set of default holidays but also allows you to create your own. This version allow you to add bigger bulbs and to play music at your own discretion. Happy Holidays with your PowerPC!