So I keep on seeing/hearing this Hyundai commercial on TV with this incredibly addicting jingle.
It reached the point that even hearing the first second or two of the commercial would immediately make me think Hyundai. (Good job Hyundai marketing. Unfortunately for you, I bought a new car just 12 months ago.) Thanks to Yahoo's frontpage (can't find the link, sorry), I now know that the jingles are the work of a YouTube-famous indie band named Pomplamoose. They do a lot of interesting covers, but this cover of Mr. Sandman is probably their best one.
(Humorous aside, when I first saw the link, I misread it and I thought it was a cover of Metallica's Enter Sandman.)
In addition, I learned that their jingle is actually a cover of an old Jackson 5 song called "Up on the Housetop".