Three Answers:
1. Autofocus Illuminator or Focus Assist Lamp
2. It is not fairly universal.
I don't know of any site that has a list of cameras that have the Autofocus Illuminator. Canon is probably the biggest user of this approach to focus.
3. Most professional reviewers see it as one of the best methods of achieving auto focus under low light conditions.
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Take a look at the Canon SD200 or SD300.
Ultra compact with Autofocus Illuminator.
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One thing I hate about my current crappy camera is that, when taking a picture in total darkness, I pretty much have to rely on point-n-pray when it comes to capturing my subject. I've seen some cameras with an orange light that comes on before taking a flash picture, allowing the photographer to get a better sense of what's in the viewfinder.
Three questions:
1. What is this feature called?
2. Is it fairly universal at this point? If not, which cameras have it?
3. How valuable is it?
As you may have seen from my previous post, I'm in the market for an ultracompact, so I'm mostly concerned with those models.

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