Canadian company 4iiii has created an attachment for sunglasses that offers athletes a heads-up display — of a sort. Called Sportiiiis, it's an array of seven colored LEDs provides feedback on your workout. When paired with a wireless Ant+ monitoring device, the lights show a spectrum representing how intense your current activity is. The green light in the middle signifies the optimal level while yellow to red lights on either side show too little or too much intensity, though you can adjust what the device considers to be optimal. If a row of LEDs just below your line of vision isn't enough for you, a single tap to the attachment will also give you an audio cue via built-in speakers.
The company is advertising its use with multiple devices measuring heart rate, speed, power, pace, and cadence, with a double tap to the Sportiiiis switching between these devices. The Sportiiiis will be available in November with prices starting at $199, which seems like a big price to pay so you can avoid looking down at your heart monitor.