My reply to http://oozinggoo.ning.com/forum/topics/why-do-you-like-lava-lamps? , I think I'll just leave this here ;)
The ever-changing interplay of motion and color. The steady, patient rise to the top, a brief rest then back down for a rest at the bottom. Light and glowing underneath with a shadow at the top, shading from dark to light, and light to dark. Blobs meeting and separating, joining and departing, sharing the warmth of the moment with each other. The ebb and flow of life displayed in a myriad of colors, shapes and sizes.