They're rare, they're weird, they're unexplainable. And yet Matt of X-Entertainment found one: The endangered Shamrock Shake! Man, McDonald's doesn't even bother to stir them up, they're served to you kind of half green, half white, and you've got to practically bring your own blender to mix them properly.
Be sure and watch the Shamrock Shake TV commercials Matt found. Uncle O'Grimacey is one deadly scary green lumpy dude, that's for sure.
Also, this line cracked me up. It's funny because it's true: "The scope of McDonald's advertising campaign has critically shifted away from actually mentioning their food during the commercials. If they do, it's usually just to let everyone know that they SELL SALADS because it gets them off the hook for everything else they sell."