Greg Hayden, chief technology officer at Luna Development, a small Windows Mobile-based business solutions developer in Toronto, Canada, is brimming with ideas for how the technology could be used - including some that don't entirely depend on a critical mass of consumers with reader software installed. Some the company is already developing into products.

Luna was introduced to the QR code phenomenon by business friends in Japan a little over a year ago. "We were immediately impressed with where we thought we could take this," Hayden says. They were convinced in fact that mobile bar code reading could be much more than it is in Japan today, and more than just a way to show consumers advertising.

One very simple notion: exchanging business card information.

Instead of printing hundreds of cards, you print a QR code on one card, or on a sticker that you slap on the back of your mobile. New business associates read the code with their phones. It contains your name, title, company name, contact information. Data capacity for QR codes is over 4,000 alphanumeric characters, plenty for this purpose. Software on the recipient's device could automatically format the data and insert it into a contact database.

That one probably does require a critical mass, if not of consumers, then of business users.

Hayden believes retail inventory is another potential application - not just for counting inventory, although that could be one use, but also to consolidate information about an item at point of sale (POS). Many computer products, and products in other categories too, carry multiple bar codes, plus serial number and SKU. All could be contained in one QR code, he points out.

This would simplify transactions by allowing the retailer to capture all the information he needs for his own records with one pass, plus print a summary of key data points that the customer might need right on the receipt.

"It's probably not compelling enough for retailers to change their whole process if they've already paid for a barcode[-based POS] system," Hayden concedes. "But if they don't already have a system, it does make sense." For one thing, using a cell phone to read barcodes would be cheaper than using expensive dedicated scanners, he says.

Would it be as fast, though, we wonder?

Hayden can think of a bunch of applications in the retail realm that might work if putting visual codes on product packaging became as ubiquitous as printing conventional barcodes is today.

QR codes could contain ingredients lists and other information typically printed on product packaging in text too small to easily read, for example. The user scans the code, which display the text in more readable form on his mobile screen - and/or he can save it for future reference. Or for a sight impaired person, a PDA could read the ingredients list and other information - adverse reactions printed on a pill bottle, for example - using text-to-speech simulation.

The list goes on. Consumers could create shopping lists at home by scanning QR codes on product packaging - and even capture QR coupons printed on the package, he suggests. One that retailers probably would not welcome is Hayden's suggestion that consumers could scan products on a shelf to automatically check prices at competing establishments.