This past Christmas I really wanted to get WiFi-enabled digital picture frames for both sets of grandparents so we could stream pictures of our family's new addition, but after lots of research was unable to find a frame that didn't require an expensive service subscription. I ended up scrapping the idea, although I did get this Philips frame without WiFi for my wife to take to work.
But things are looking up, as I just discovered this recently launched Kodak EasyShare frame with WiFi that lets you share photos over the Internet for free. And it's only $30 more than I paid for the smaller Philips frame. Shhh, don't tell my parents or in-laws.