You can get custom or the pre-cut mats to the 3x2 ratio. It's all archival so it will cost a little more than the non-acid free boards that self-destruct after a few years. The mat board fits within the dimensions of a standard sized frame or molding like 8x10, 11x14, etc. That's the way it has always been and the way it is usually displayed.
Ah ha. The 'secret word' is "Digital". Hate those things. My digital photo frame goes 45 minutes before it dies... then half a day to recharge. I must I have an early model. So in retrospect, no, I have never seen. You could resize the picture to the 3x2 ratio then transfer. It worked for me years ago, but since then the DPF would be the last place I'd put pictures. I like the iPod & iPhone better.
