Since the dawn of YouTube, fans have been melding their own amateur video with the music of their favourite bands.

The results have been mixed. The picture that immediately comes to mind is someone bouncing around their bedroom - dancing and lip-syncing, when they shouldn't be. One of the first viral videos established this prototype: nearly 20-million have watched two Israeli girls rock out to the Pixies' "Hey."

The success of the clip (http://tinyurl.com/l37de) had more to do with cute teenagers dancing than anything else. But occasionally, fans have created startling, worthy videos.

The best of these videos make use of film in public domain or lifted from copyrighted material (which means that some of these clips could at any time be removed from YouTube).

Spin magazine recently brought Bruce Springsteen and Win Butler of the Montreal indie band Arcade Fire together for an interview. The Boss' first comment to Butler was to voice admiration for a fan-made video for the band's song "My Body Is a Cage": http://tinyurl.com/yt5o6y.

The video, made by J. Tyler Helms, matches the song with footage from Sergio Leone's 1968 spaghetti western "Once Upon a Time in the West." It's somehow a perfect fit for the sombre, haunting song.

On his blog, Helms sounded amazed at the success of his fusion: "The Boss himself. Honored doesn't begin to say it."

A similar effect is aimed for in a video for Built to Spill's "Car," which Mark Saldana illustrates with Library of Congress footage, mainly of - you guessed it - cars. Though much of the video (http://tinyurl.com/y9mc5f) veers off-road with irrelevant old stock footage, the basic premise is sound.

Weirder still is a reimagining of Mark Romanek's classic Nine Inch Nails video for "Closer" by two fans who identify themselves as T. Jonsey and Killa: http://tinyurl.com/ezmmv. Instead of Romanek's creepy visuals, we get footage from "Star Trek," scratched and coloured to roughly match the style of the original video.

The song (which includes explicit lyrics) makes Spock look terrifying.

But perhaps the most unlikely video mash-up is one for a little known band Health, whose video for the instrumental song "Heaven" takes from Werner Herzog's 1974 documentary, "The Great Ecstasy of the Woodcarver Steiner": http://tinyurl.com/2lmqvt.

An obscure film for an obscure band, sure. But together, the slow-motion film of a ski-jumper and the band's noise-pop sounds yield something more. It's been hailed by the indie rock music blogosphere, and website Pitchforkmedia.com listed it among 2007's best music videos.

Not only music is re-visualized online; standup comedy bits are often brought to life. One video-poster named Thorn2200 (who identifies himself as a 15-year-old) has created nearly a dozen Lego-animation videos to correspond with Eddie Izzard's standup.

Here, he illustrates Izzard's "Death Star Canteen" bit, complete with a miniature Darth Vader: http://tinyurl.com/2sqgsz.

How bands and other artists greet these unofficial videos can be awkward. Have them removed, you risk alienating your fans; leave them and you give up a part of your branding. Music videos have long helped establish an artist's image, but could the Pixies be happy that millions now associate their song with two goofy teenagers?

Many bands have held competitions for fans to create videos, including the Decemberists, Modest Mouse, Shakira, Incubus and the Yeah Yeah Yeahs. Others have circulated video cameras through concert audiences to create multi-perspective videos, including Daft Punk and the Beastie Boys.

Acts are increasingly giving up at least some control, leaving them sometimes wondering what their role is in this new post-MTV democratic world of music videos.

For the unofficial video for Spoon's "Don't You Evah" (http://tinyurl.com/yp38wh) produced by Wired magazine, the band gave its blessing to the robot-dancing clip. If you look closely, though, you can spot Spoon frontman Britt Daniel on an escalator - only a background figure in his own video.