Half and Half was the inspiration for the Dual Beer Glass from glassblower, and founder of the Pretentious Beer Glass Company, Mathew Cummings.
The individual chambers of this hand blown glass keep two beers separated until the drinker takes a sip. At that point, I'm not sure if the two beers will then get combined in the glass anyway, or if the twisted design of the interior wall keeps them from spilling over into the other chamber. There is also the added bonus of being able to see the colour and smell the aroma of the individual beers which is typically lost when blending beers. Due to the nature of handmade glassware, the dimensions will very slightly but the glasses are approximately 5~6" tall, 3" wide and hold 10~12 oz.
I'll admit, I am curious about them, but at $35 each (or 4 for $125), I'm not sure if I'm curious enough. The Pretentious Beer Glass Company also produces a variety of other pretty cool hand blown glassware that's designed specifically for craft beer. You can order these and see all the other glassware on their order page.