DISCLAIMER!!!: This project can be EXTREMELY dangerous if you do not know what you are doing, in the case of this system, the x-rays are the least of the problem, however a flyback transformer can give you a nasty shock that could even kill you in some cases. The X-ray emissions from this project are not dangerous if you understand the physics of how x-rays are produced and what type they are. Regardless, use shielding. I am NOT responsible for any damages to people or property if you attempt this.
Now that that's aside,this is a video demonstrating my X-ray source that works quite well. It uses a high voltage triode driven by a flyback transformer driven by a traditional Mazilli ZVS circuit. You can see the schematic I used here http://www.instructables.com/id/ZVS-Driver/
The ZVS or zero voltage switching circuit is used to drive a flyback transformer from a television set, which the accelerates electrons inside of the triode. The electrons slam against the metal plate and release their energy in the form of an x-ray. It is not a point source, so don't expect to x-ray your friends. This project was built with the intention of producing x-rays with components I already had or wanted to build. This device fulfills its operating requirements as I do not need a high energy point source at the moment. Eventually I will buy a real x-ray tube and test it on this setup. This complete setup will be used in part with an x-ray intensifier and fluorescence spectrometer to measure light output from the screen.
For more projects and follow-ups on this project, see my blog at http://Spectrhz.wordpress.com
UPDATE: This particular video is one of a failure to produce x-rays, see my newest Instructable on why it failed, and how I made it produce x-rays.