Blinking Eyeball Rings
In retrospect, I think that I made an inferior choice when selecting my wife’s engagement ring. But then these rings developers at Keio University in Japan were not available at the time.
[Yes, it's clearly an engagement ring. Observe: third finger, left hand.]
The PYGMY robot rings blink according to different settings, including voice recognition, finger activity and remote control. They are, sadly, not yet on the market. So you may need to delay your wedding. In the meantime, watch a video of them in action at the link.