Finally snagged a 6-pack of Zima after last having it around 2008 and then missing out on last summer's limited re-release. Still tastes like a malted Sprite, and still hits the spot on a hot summer night when you don't want to be hitting the harder stuff.
Around the time the popularity of Zima peaked, there was a magazine article about making a homebrewed version from scratch. IIRC it involved brewing a light ale, then treating it with activated carbon slurry to strip out nearly all the color and "beery" flavor, filtering, then adding citrus oil. At the time, it fell squarely into the category of "you would only do this to prove you can, because why would you go to all that trouble to make something you can buy at the local convenience store". Now that it isn't being mass-produced any more, maybe it's time for you to take up homebrewing.