Joe Kukura

Everyone has been dying for a look at the top-secret Google Glass augmented reality glasses. Several New York City subway riders got a look at them for free last weekend because Google co-founder Sergey Brin just plain showed up on the subway wearing them, in everyday street clothes, with no security detail—even though they are perhaps the most-anticipated new gadget technology of the decade.

Wait a minute. Sergey Brin is the 13th-wealthiest person in America, has a net value of nearly $20 billion, and he rides the subway when he visits New York City? If you're curious, that ride cost him all of $2.50.

Nonetheless, Sergey Brin wore Google Glass on the subway, and was spotted by self-described "Wearable Computing and Augmented Reality enthusiast" Noah Zerkin. "Yeeeah..," Mr. Zerkin wrote on his Twitter post announcing the encounter, "I just had a brief conversation with the most powerful man in the world. On the downtown 3 train. Nice guy." And indeed, Sergey Brin was wearing those yet-to-be-released augmented reality glasses that let you perform computer functions using just your eyeballs.

"He was probably playing Words With Friends during your conversation," snapped back one clever Tweeter.

Noah Zerkin, the "regular guy" who spotted Brin in the wearable computing glasses, is not actually that regular of a "regular guy". Mr. Zerkin works in the augmented reality field, and is actually working on a pair of these glasses called the Vuzix M100. These will not be competitors to Google Glass, they are likely to use the Google Glass technology. Google Glass will be "fragmented" like the Android operating system. Plenty of different competing devices will be able to use the same basic Google Glass operating system, and the Vuzix M100—which were on display at CES 2013—may be one of them.

This is not the first time we have seen the Google Glass augmented reality glasses in public, but it may be their most unexpected appearance. Sergey Brin has worn the glasses in public before. Designer Diane von Furstenberg wore them at New York Fashion Week, Sergey Brin has done interviews in them, and skydivers wore Google Glass to make a spectacular video from this year's I/O Conference.

The Google Glass glasses are expected to be available in 2014, and the presumed cost will be around $1,500.