There have been a few items in the rumor mill about Google either investigating or planning retail stores, not unlike the Apple stores that famously dot malls and upper-class shopping areas around the world. 9to5 Google reported a tip from "an extremely reliable source" citing a 2013 rollout schedule for a Google store. Then the Wall street Journal, itself a pretty reliable reporter of the inner workings of Google, reported the same thing. The WSJ omitted a time frame, and noted that the 2013 claim may not be accurate.
A Google store would naturally focus on Google hardware, such as it is: you could definitely imagine Nexus phones and tablets, Chromebooks, and maybe even a few Google TVs littering a showroom.