Sorry guys, i know its ANOTHER one, but I found an effective way
This tutorial is based on xz64's tutorial
Lightsaber (03) and Joe's tutorial
PhotoRealistic Lightsabers tutorial.
Personally I preffer the original trilogy sabers (4,5,6) better than 1, 2 and 3. Here is a pic from the original trilogy.

Now heres the tut.
1. Open your pic and if you have to clone stamp the saber out.
2. Create a new layer filled with black and change its blending mode to screen.
3. Make a selection of your saber and fill it with white
4. If required blur it say 1 pixel or something
5. duplicate it twice and select the bottom layer
6. blur it to create your coloured glow and then blur it again to create the base glow.
7. Apply fade with the blending set to screen mode.
8. select your 2nd layer and change its blending mode to colour dodge.
9. Blur it to create edge glow.
10. select your bottom layer again (coloured and base glow layer) and select variations.
11. Make sure u press oringinal and then I like to click red then magenta then red again.-for variations see my next post
12. Now open variations for edge glow and u can either click original or leave it the same colour it was before and click ok
13. apply levels to edge glow if required and/or adjust hue/sat
14. TADAA!!!!!!!