DeviceGuru writes with this excerpt from LinuxGizmos: "GlassUp, an Italian startup, has started taking pre-orders on Indiegogo for an Android eyewear display system billed as a simpler, lower-cost alternative to Google Glass. The GlassUp device is a receive-only Bluetooth accessory to a nearby mobile device, providing a monochrome, 320 x 240-pixel augmented reality display of incoming messages and notifications. GlassUp was unveiled at CeBit in March, and is now up for crowdfunding on Indiegogo, where pre-sales opened today ranging from $199 to $399, depending on whether it's a pre-release, pre-production, or full-production version. This is less than a quarter the price of the $1,500 Google Glass Developer Edition. Already almost two years in development, GlassUp is expected to ship to presales customers in Feb. 2014, around the same time Google Glass is expected to ship in commercial production form."
And for Google Glass itself, there's at least one project to bring Google's own hardware an alternative operating system