I do know about pano2vr and pano2qtvr, but I don't have the money to purchase a license. The free version of pano2qtvr does not allow you to create thumbnails in the mirror ball format. I liked Bill's link, I will definatly look into trying that.
As for using the image from nodalninja.com, I appreciate you giving permission. I am a web developer and I know how important it is to check for copyright and ask for permission. I will let you know what image I use.
I've always considered this a flawed Action as it doesn't produce a geometrically correct reflection. If you look into a real mirror ball, you will see the horizon positioned at about 0.7 of the radius from the centre. The action puts the horizon at exactly 0.5 of the radius from the centre. This means that the sky area looks considerably smaller than it should be. The mirror balls produced by Pano2VR and Flexify get the horizon in the correct position.
If you just want a mirror ball thumbnail, you can make a good one in Photoshop:
1. Open the equirectangular image and flatten if necessary, to make it the background layer.
2. Image->Image Size . Uncheck constrain proportions and set width to 50% (hit OK)
3. Filter->Distort->Polar coordinates (select Rectangular to Polar)
4. Tweak it with Filter->Distort->Spherize at 95% (adjusts horizon position)
5. Crop away the area outside the circular image using a circular selection (or fill with black or white).
You can, of course, make this into an Action for repeated use.