How to Shop in Osaka: the Art of the Discount
Osaka is famous for the phrase, "負けてください！" (makete kudasai!), a phrase used in haggling to mean, "Give me a discount!" This works best on big-ticket items like TVs and such, where the best you might hope for is for them to waive the tax.
Another way is when a Japanese business has decided to create an online site where the price advertised is cheaper than offered at their brick-and-mortar counterpart. Case in point: today I was able to get ¥1,200 (about $10) knocked off of a replacement hard drive at the popular electronics store, Joshin (basically the Best Buy of Japan) because I was able to show them the relevant entry on my iPhone. At the very least, it saved me the hassle of waiting a couple of days for Amazon to deliver for the same price.