Your holiday guide to credit card innovations and gadgets

It's been some time since I last updated you all on the must-have gadgets and gizmos related to credit cards. To make it up to you, ahead of the holidays, here are the latest payment card innovations -- in the form of a Square, Piece of Cake and a Nintendo controller.

Square lets card payments go mobile
You've always got your iPhone handy -- seriously, can you stop texting for five minutes? Now, with a new device known as Square, you can accept card payments wherever you and your mobile phone go.

A Square screenshot. Photo courtesy of Square

Square is the latest creation from Jack Dorsey, the brains behind microblogging Web site Twitter. As for Dorsey's newest innovation, the small plastic Square device plugs into a cell phone or iPod's headphone jack. It requires the shopper to only have a credit card and e-mail address to submit a payment and then get an electronic receipt.

This video shows you Square in action.

In the current economic environment, why encourage credit card use? The device's creator isn't shy about his dislike of cash. "I, for one, hate getting change," Dorsey tells the Los Angeles Times. "I just can't stand it." Square's success could depend on whether regular cardholders also hate change more than they hate being in debt. 

Splitting the bill with plastic becomes a Piece of Cake

Piece Of Cake. Photo courtesy of Yanko Design.

Square may be cool, but when splitting a bill with friends, consider going circular.

Let's say you're dining with friends at a restaurant. The bill arrives, and everyone takes out their credit cards. Since you only ordered soup, you don't really feel like splitting the bill evenly with your hungrier friends who rang up much higher meal costs. 

Enter the Piece of Cake device, a concept created by Yanko Design. "By using this device, each one can pay for just what they ate using their CC [credit card]," Yanko Design explains on its Web site. "The screen displays the total items consumed and you select your share to be automatically calculated."

The device is just a concept right now, but as a math-phobe, I like the idea of removing the stress of calculating each diner's portion from the total bill. I also like that the Piece of Cake device, pictured right, includes a dish described as "fried rice pasta" (!) alongside conventional food items like tomato soup and chicken salad.

Nintendo controller holds your cards
Since reliving the '80s continues to be a popular pastime for many, what better place to keep your cards than a case resembling the classic Nintendo Entertainment System video game controller?

Branpesto's product was designed to carry business cards, but I'm guessing it could hold similarly sized payment cards. While a credit card that comes out of an NES card case is unlikely to be refused, a business card that comes out of that same holder just might be.

Still, for those of you who want to celebrate those bygone 8-bit days, "the NES Controller Business Card Case is ubergeeky, as it essentially is a replica of a video game controller," Trend Hunter magazine explains. "The controller is complete with 'A' and 'B' buttons as well as 'Select' and 'Start' buttons." You know you want it.

See related: Still more credit card gadgets and gizmos you cannot live without, More wacky, wonderful payment card innovations and gadgets