I'm guessing it has a little Twitter API as the background that measures:
:) =) :] :D vs :( =( :[ ;(
And then streams every tweet on to their black backdrop. The counter also resets every day to give a global smileage tally.
Measuring Smiles
Earlier today I ended up on Chunk's website. They're a digital agency in Glasgow that have been measuring smiles since 2001. How you may ask? Well, via their background. Oh and a little counter guy on the right.
It's a sweet little idea, but the only downside it that it runs in Flash. Please Chunk, make jQuery version and it'll make everyone, anywhere, smile.