If you're tired of getting pre-made digital photo frames that kinda work but kinda don't, then give this RedPost Linux photo frame a shot. Sure, it costs $549, but comes with a 19-inch LCD monitor, a 200MHz CPU, 802.11b/g Wi-Fi, and is custom-built running Damn Small Linux.
If you're wondering why you'd pay nearly $600 for a photo frame, well, you'll have to remember that this runs Linux. Which means you can pretty much (as long as you have some programming knowledge) extend it to do anything. Streaming pictures off your PC, showing stuff off of Flickr, or anything else you can come up with.