Crazy Frog is a popular Swedish project of Erik Wernquist, which appeared in 2003.
The most popular composition that became a hit is considered to be Axel F - the cover version of the instrumental composition "Axel F" (from the soundtrack of "Beverly Hills Policeman" movie) by composer and musician Harold Faltermeyer. Although Crazy Frog's version of this tune is actually based on the 2003 version by Murphy Brown and the Captain Hollywood Project.
Other popular hits from the project include "Popcorn" and "Jingle Bells.