CyanogenMod is, as the website puts it, “a heavily optimized build of Android”. It includes dozens of new features when installed on Android devices and, with over thirty thousand users, is one of the most popular Android custom ROMs. So why, when Android is open source, is the guy behind CyanogenMod.com in trouble with Google?
Well, it’s because he’s also modified Google’s own applications - including Maps, Market, Talk, Gmail and YouTube – and these aren’t open source. This means he’s not allowed to tinker with them and redistribute them (even though they'll only work on the original device). He says he hopes he can work something out with Google. Fingers crossed. [Sources: AndroidAndMe.com; Cyanogen on Twitter]