Sick of waiting for the Nexus 4 to go back in stock and you have a random LG Optimus G lying around? Well here's a project for you. XDA recognized developer Rohan32 (EDIT: My apologies. Team CodeFire were the ones who came up with this; Rohan32 is maintaining and adding fixes) has come up with a method that makes your LG Optimus G into a full blown Nexus 4. No, it does not change the hardware of the phone, but since the Nexus 4 is based off of the Optimus G, a lot of the same internal stuff is there.
Before you get your hands dirty, please remember to be careful with this hack and know what you are doing before you get into this. The developer puts in red and all caps that it is "so uber-hacky it is incredible." Rootz, XDA, and Rohan32 cannot be held responsible if you brick your phone. Please read all of Rohan32's thread to make sure you know what you are doing. Bricked phones break my heart.
Now, on to the good stuff.
This process will convert everything on the phone to the Nexus 4 equivalent. This will allow the user to flash anything that is in the Nexus 4 development forum. This includes ROMs, kernels, or other mods. You can even run AOSP if that tickles your fancy.
There are a few problems with the process still (again, uber-hacky). Right now, only 8 of the 16gb show up to be usable and the capacitive buttons don't work, but of course, the Nexus 4 doesn't have capacitive buttons. For some reason the volume buttons are also switched, but Rohan32 is hard at work fixing bugs and improving the process.
If you wake up every day wishing that your LG Optimus G was an LG Nexus 4, today is your day. Let us know how it goes.