I made a video series where I also used my pendulum to try and find out more information concerning the various orbs that I've documented on camera and in meditation. The dowsing portion of this video series is in part 3 (I believe).
Either there are different species of orbs or some or all orbs can shape shift. I do believe that some orbs are here to help us. Those more aware or who chose more awareness continuation concerning orbs (which is just a name for "The tip of the ice berg") are also those whom experience more amazing possibilities (like I do concerning orb activity and more).
Also, be sure to contact your local orb or higher self (god or universe) for more information
Orb Awareness: Part 1
http://www.youtube.com/watch?v=-7Szj_OeEGs
Orb Awareness Part 2
http://www.youtube.com/watch?v=pS9uXioMu_8
Orb Awareness Part 3
http://www.youtube.com/watch?v=pjAclRtW_zs