When artists Justin Gignac and Christine Santora want an iPod, they simply paint it – and sell the canvas for the same price. Charlotte Philby talks to a couple with a creative take on economics

What do you do if you really want something, but you just can't afford it? If you're New York-based couple Justin Gignac and Christine Santora, the answer is easy: you simply paint a picture of the thing you want, sell that painting for the price of the thing it represents, and use the profit to buy whatever it is you were after. Don't believe getting what you want could be that straightforward? Just visit the pair's online gallery and shop at www.wantsforsale.com for evidence that I want does get.

Since launching their website two years ago, the creative pair have transferred a whole range of items from their "want" to their "got" list. Among these are luxuries including dinner at Nobu, and a pair of gold aviators, and less tangible desires, such as a good night's rest. "Sleep was one of the things we were deprived of when we first started this project," explains Christine, 25. "So we painted a few Zs on a canvas, and asked visitors to buy us some much-needed bedtime."

As this example shows, wantsforsale isn't just about making money to accumulate stuff. The "Sleep" painting didn't cost the buyer anything, but just shifting the piece gave the couple enough of "a sense of achievement" that they could sleep easy for the next couple of nights. It is "sales" like this that makes the project really worthwhile, Christine explains, speaking from her and Justin's apartment in Greenwich Village: "More than anything, it's about having fun with art." While making the cash to buy little extras is a bonus for them, the project is also a record for this young couple. In years to come, it'll be fun to look back and see the things we wanted at this point in our lives," says Justin, 28.

The idea of wantsforsale started out in 2007 as a creative personal project. Yet, within two weeks of launching their website, the couple had sold their first eight acrylic paintings, and had received 40,000 online hits. After another successful few runs, the potential of what they were doing become strikingly apparent. "We don't know exactly who buys our work," says Justin. "But we have customers in Europe, Canada, South America, Asia, and realised that we could be making a hell of a lot of money for people who really need it, if we set our sights that way". To this end, the couple applied their want formula to fund-raising. "First off, we sold a picture of a toilet bowl for $1,000, which is how much a particular charity needed to develop a sanitation system for people without one in India." Since then, the couple has raised $5,000 for various charitable causes.

Furthermore, the project has been used as a political weapon. "We drew a series of paintings of Barack Obama during the electoral campaign," says Justin. "Anyone who donated $100 to Obama's cause, through us, would get one of these limited-edition prints." One Frenchman was so taken with the idea that he raised $2,300 for a painting. All in all the pair amassed $7,500 for team Obama. "It was quite an achievement," Justin says. "After that, a lot of people wrote to us after that to thank us for not drawing John McCain".

Despite their success as political campaigners, the couple insists the project remains an artistic rather than social endeavour. For good or for bad that may be, but one thing is for sure: their fundraising tactic brings a literal new meaning to the term political canvassing.