apple tv makes this incredibly easy from iOS devices, but i'm assuming that doesn't fit the bill
Indeed and i'm all the richer for it haha....
you don't even have to "pair" devices or set anything up - i was well impressed when we had visitors recently who wanted to show us the photos they took at our wedding, and they just pressed a button on their iphone (having never set foot in our house before) and they were instantly displayed on our TV!
I think as Chromecast gets going that will fit the bill nicely but a) its not released in the UK yet but you can import them at a premium and b) not too many apps support it at the moment but that will quickly change.
On the note of Apple TV and simplicity, I wanted to transfer a file to my wifes phone - after trying to upload it to dropbox and it taking ages I read about an App called File Beam (Touch to Send) and basically if you have two phones with NFC, just select the file in file manager, choose share and select file beam and then touch the phones.... this will instantly pair the phones over bluetooth and make the transfer.... none of this "switch bluetooth on, make the device discoverasble, search for the device, select it, pair it, put the pin number in....." business.
If they can replicate that in Smart TV's and even ICE then will make things so much simpler I think.