Hiya Raj & Phil,
If I recall correctly (I only used it a few times so maybe others use it different ways) I used it to put in a field that didn't show on the site that would tell me where the information came from. It would be similar to what people do in magazine advertising where they ask you for the code from the ad that you are calling about to see what publication or medium is working best for them.
This way you can duplicate the form multiple times and just change that field and upload a different copy of it to different websites. When you get the form results it will come with whatever you have entered into the value field (which I don't think had too many restrictions in the old version, not sure on this one). This would then tell you which website they sent it from so you can tally which sites are working well and which ones aren't.
@Raj: When you get the form results it should already automatically give you the time/date/IP stamp from each results page. Have you already tried it and you're not getting this info? If that's the case let us know as I'm pretty sure Scott said it should work always now, unlike the flash version which only worked if you "didn't" alter the results email at all.
Hope that helps
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