Need to accept credit cards, but don’t want the hassle or expense of having that large credit card machine?  Squareup is offering a very interesting solution.  With a simple accessory that fits into the headphone jack on your phone, you can now scan payment cards.  After you have made the sale and scanned the card you can then text or email the receipt to your customer.  Squareup is also donating a penny for every transaction you make to a charity of your choice.  Availability is unknown at this time as is device compatibility.  We do know that it appears the iPhone and Motorola Droid are supported per the images on their site.  The future of payment acceptance is looking very convenient and green for those who choose to go this route.  Oh, and you can lookup your receipt per their site via your phone number and transaction amount as a very convenient bonus.