Another Photoshop experiment. To create the background in this image I used a radial gradient. A chrome filter was applied to the gradient.
The wispy lines were created by using the pen tool to create a path, you then stroke a path with a brush by right clicking on a path and selecting “stroke”. If you have a fat brush then your path will be stroked with a fat brush using the foreground color. After that I just added some glow and drop shadow to the whiskey lines.
Then to create the different nebular colors I added another layer on top of everything with a radial gradient. Changing the “blending mode” for the layer is essential. Experiment. Repeat this process with other layers using different colors and blending modes.
It’s still kind of looks like you’re looking down into a cup of coffee.