It's not the first time that rumors have surfaced of Google working on some heads-up display glasses (9 to 5 Google first raised the possibility late last year), but The New York Times is now reporting that the company is not only working on them, but that it's set to release them by the end of this year. Citing "several Google employees familiar with the project," the paper's Nick Bilton reports that the glasses will be based on Android, pack 3G or 4G connectivity, plus GPS and a range of sensors, and cost "around the price of current smartphones," or somewhere between $250 and $600. They're also said to include a low-resolution camera that can monitor your surroundings in real time and overlay relevant information, although Google is said to be paying attention to potential privacy concerns, and "wants to ensure that people know if they are being recorded by someone wearing a pair of glasses with a built-in camera."What's more, the Times says that none other than Sergey Brin is a "key leader" on the project, with another being Google engineer Steve Lee, the creator of Latitude . Notably, Bilton also says that Google sees the project as an "experiment that anyone will be able to join," and that the company is not currently thinking about potential business models for the glasses, which could suggest that they may be more of a small-scale hobby than part of a major push into consumer hardware