From 3GVision, a bar-code reader that is currently the best one available as Freeware in Windows mobile application. I've tried and it is by far the best that I've tried. You can even try and make your own barcode using their very own online barcode creator. You can visit this link. With the link provided, you can embed a URL redirecting to your site. It's quite useful if you have a personal website. Just put a QR code to your business card and when it is scanned using I-Nigma, they'll be redirected to you site - cool isn't it.
Just go to their website and download the latest version - click here. By the way, check-out the encoded message below that is made from i-nigma website as well. Use i-nigma app to reveal the message. By the way it works great with my Omnia 2.