Hi,
First off thanks for all the comments! Glad everyone enjoyed the pics.
As for the technique:
1. Wide lens since it's hard to predict where in the sky lightning will appear. My 18-55 kit lens in this case.
2. Some solid place to keep the camera still. These are all long exposures. I used a gorilla pod wrapped around a window grill.
3. Remote preferably with a lock. You can hold a regular or wireless remote button as well but it just gets painful. I used a Chinese remote purchased on ebay which was linked to on this forum.
4. Set the focus to infinity and the lens to the widest focal length. You can also play around with aperture but I stayed with F numbers between 8 and 16. I forgot about the focus in the first few shots I took but I do like some of them.
5. Make sure your on ISO 100. Knock off Shake Reduction. Personally I don't think it should be on as a default
6. Switch to "Bulb" mode on the camera.
7. Trigger exposure and lock it or hold the button down.
8. Keep the exposure going till you see some nice lightning bolts or when it's taking too long. That was around 1 min in my case but it depends on the ambient light levels so you need to find out. Keep in mind some cameras including my K20D take a dark exposure for noise reduction which takes as long as the original exposure. Be prepared to wait
9. The blue is because I set the white balance to "Tungsten." You can do this post process if your shooting RAW.
This same method should work for fireworks too.
Cheers,
Nirudha