Ages ago I made a little Arduino hack which was a simple LED matrix with three faces; happy, neutral, and sad. I recently found a photo of it so thought I’d post it. It was called Harold. I’d like to say it stood for Helpful Assistant Redisplaying OnLine Data but in truth I just like the name Harold. :)
Harold monitored my twitter mentions and when somebody @-ed me, Harold would smile. After around 30 minutes had expired he returned to a neutral face. If I’d had no mentions for a couple of hours he’d have a sad face. He was actually really handy, sitting on my desk, telling me if I had been mentioned on Twitter. So I could potter on and only check Twitter if I had an @ to read.