Oreo has been working hard to celebrate its 100th birthday (see: Birthday Cake Oreos ). While we spend a fair amount of time on HuffPost Food voicing skepticism of various food ad campaigns (see: Skittles' bestiality ad ), sometimes we've got to give credit where credit is due.

The Oreo Daily Twist campaign is pretty simple, but executed exceptionally well. Each day for 100 days, Oreo posts an image to various social channels of a cookie modified to represent a current event. This week is Elvis week, so on Tuesday the image was an Oreo cookie sculpted to look like Elvis . In recognition of the Mars landing, the filling was red with adorable rover tracks.

We've posted a few of the images before but below we've collected all of our favorites so far. The campaign ends in early October so there's still over a month of customized Oreos to go.

Check out some highlights: