Motorola releases Moto X kernel source code2
To be clear, this is not the full source code post including the binaries that would be necessary for creating a custom ROM for the Moto X. This is just the kernel source code, but that does still have some very nice uses for those who like to mod their devices. This code can be used to create custom kernels, which could be used to overclock your Moto X, or boost power efficiency.
If you have the coding skills to create some custom kernels from the code, you can grab the files for each of the models at the source: