I actually started out looking for a network wall clock. I just wanted something that could be easily synchronized. My search turned up some rather expensive solutions designed for schools and other organizations. All most did was tell time although some had intercoms and alarms built into the system. Still, going from a $20 battery operated clock to a $300 network clock seemed like a stretch.
My next idea was to find a way to build one. Most of these clocks used large custom displays. They might even be very power efficient and have great viewing characteristics but I suspect not. I didn't analyze them to any depth given their high cost. On the other hand, an LCD display would work just fine for my purposes and the plethora of digital photo frames came to mind.
Most digital photo frames are standalone devices but a few support Ethernet or WiFi. These seemed like good candidates. Even a 7-in screen would be easy to read from a distance with only four digits on the screen. Some systems even have alarm clock features but I have not found any that would put up a big, bold clock. Most seem to like tiny clocks interleaved with photos.
This brings about the programmable part. The horsepower to display hi-res images is more than enough to handle the job I wanted to do. Unfortunately, these devices are so closed that they make conventional lock look easy to crack. I can understand why vendors want to lock down their system. They tend to assume a very dumb consumer wanting a limited set of functions. Likewise, returns are not good business and any level of complexity raises the number of returns.
Still, I was hoping there might be someone who had hacked into a WiFi photo frame. Better yet, it would be great if someone simply sold one that could be reprogrammed. That is probably too much to ask for. I haven't found one that has been hacked either.
So it is back to square one. I have plenty of dev kits around with more than enough smarts to handle the job. Matching up a large LCD display is the hard part. It also tends to be expensive. The digital photo frames keep the cost down because of volume.
So it is back to the drawing board for now. It is too bad because a WiFi photo frame would be a great platform for other projects. I have seen a couple write ups about units being used as remote viewers for webcams. It is too bad that vendors don't make a programmable platform available because they might get some ideas on features to include in their standard products. Pairing photo frames with smartphones and other mobile devices could lead to some interesting solutions.