This was not working in my shop, so I had someone fix it. I take no credit for it. Thanks to Rob for fixing it and credits to the original authors.
These are the modifications:
-This modification works with any currency format.
-This modification works with the number format setup in your currencies.
-Workaround for Javascript disabled clients ( standard output in that case )
-Work with special price.
-Show change in old price and new price.

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