For those geeks who are interested in the technology used for radiation therapy, this is some info on the machine that performed the treatment on me.
It is made by Varian and the system is called
Trilogy. This system does not use a tube, rather you lay on a platform and the arm swings 360 degrees around you. One other thing of note is the system shoots the beam and is guided by a panel that has a large set of plates/fingers that constantly move in and out and provide the outline of the area being targeted.
Many people mention clicking. I believe this is tomo-therapy type systems that administer dosage in slices thus the clicks whereas Trilogy is 100% real time adjusting the dosage so there is no clicking or fixed slices.
Lastly, the "beam on" time is 60 seconds in each sweep around the body. It goes around counter then clockwise for a total of 120 seconds. I noted the time once and it was 5 minutes from the time I laid down to the time I popped off the platform.