This hack* is to do with identifying which of the 1-in-5 bars is a winning wrapper (or not) for the Cadbury "Score a Freebie Bars Promotion" that expires at the end of this month. Get in quick before all the promo bars are replaced with new stock!
Update: This deal/hack/promo has been just a tad popular (gee, thanks everyone!) and it may well be that all of the winning bars have already been taken at your local store. It has been reported in the comments that some of the larger stores/chains have either stopped redeeming bars or taken promo bars off the shelves entirely so you might have more luck at smaller chains or service stations.
This works for pretty much the whole range of medium bars, in approximate order of easiest-to-identify-to-hardest:
40g TimeOut
52g Cherry Ripe
50g Crunchie
46g Picnic
39g Twirl**
60g Boost**
ONLY the winning wrappers have a barcode printed on them on the inside of the wrapper. This barcode can be identified on the outside of the wrapper by looking for VERY slight indentations as in the attached scan (a thin red square has been drawn around where you should be looking). Reflect the bright store lights off the wrapper and if you are lucky the indentations will be visible in approximately the same place.
You have to buy your first bar (which are on special/clearance at the moment at most major supermarkets), but after that in theory you can redeem the winning wrapper for another winner carefully selected by yourself, ad infinitum.
As far as I can tell, posting this does not invalidate or contravene the terms and conditions of the promotion:
http://www.cadbury.com.au/Competition/Score-a-Freebie-Bars-P…
Enjoy!
*There was only a "Freebie" tick-box when submitting the deal, so I ticked that. If there was a "Life Hack" or "Other" tick-box I would have ticked it when creating the deal, my apologies to all the Captain Literals out there who have said this is not technically a bargain, they are probably right ;)
**Twirl and Boost are harder to identify unless you know exactly what to look for and have a really good eye.
LOL this is one awesome post. How can Cadbury have been that stupid as to not realise it. Its not like its the first time running the promotion. Mars have been promoting free bars for almost 5 years already.