Detect change in file, automatic upload?

Does anybody know of a client (Windows XP) that would "watch" a designated file (html) and detect a change (whether it be change in filesize, change in last modified date on windows, etc) and then automatically upload the file to a server I designate? I have a file that updates sporadically at 1-10 minute intervals and it would be extremely convienient if I could use something like this to automatically upload this updated file rather than rely on a scheduled upload every x minutes.
I'm currently using "AutoFTP" to upload the file every two minutes, but it would be MUCH better if the file could be automatically updated in "real time" rather than assuming it will update in 2 minutes. (Also, this way, I don't waste uneccessary bandwidth uploading unchanged files, but this is not really an issue).
It would be great, too, if, like AutoFTP, it could run in the background so it doesn't impede my work on my computer as it is uploading.

If anyone can give me a point in the right direction, it'd be greatly appreciated. Thanks.

-Mike

No ideas?