Here's a GREAT article from YNAB (You Need a Budget) about all those "savings" at the cash register:
http://www.youneedabudget.com/2008/wow-you-saved-more-than-you-spent
I've thought of that myself at supermarkets where they are so excited to tell me how much I've "saved".
I hope you find it funny, too.
And if you actually need to budget, there are links to his site. I recommend it and his program as practical and easy to use and at a budget-friendly price. :)