Some soap bubbles with procedural color swirl materials.
There are five bubble materials; they are all the same except for the color distribution. The bubbles are on layer 1, the camera, DOF empty and background plane are on layer 2.
I suggest using an HDR for lighting this scene. There are some great ones at HDR LABs All their HDRs are licensed under the Creative Commons Attribution-Noncommercial-Share Alike 3.0 License.