Recently there has been a whole bunch of talk about Icelandic superheroes Sigur Ros
and their claims of plagiarism all over the world. The band is very vocal about their hesitation to provide tunes for selling products, although they often lend their sonic creations to films, TV, and charity. After saying no quite a few times, they've noticed a suspicious pattern of close-to-the-same rip-offs appearing in commercials.
The pattern is this: Sigur Ros decline an offer from a company, the company goes ahead and arranges a pseudo-rendition of the song, and then uses it with no repercussions. Although it seems harmless, it is somewhat of a sticky situation. The companies are using the well-known tunes of the internationally acclaimed band to further their products, something that is patently against the band's wishes.
Making matters worse, it is very difficult to prove (on an international scale no less). Sigur Ros issued a blog post (entitled "Homage or Fromage"... Ha!) to explain their feelings, and to implore your eyes and ears. It's worth a read for fans of fair use all over the world.
Check it out here