Now we can all admit to having at least seen a few of them (if not made one or two along the way), but which ones are truly good? I pick out a few of my own. Now please note that the authors listed here are only uploaders of the videos. They may not have had the drive to actually create them, but if they did... good on them for doing so.
1) Crazy Loopin - AMV Dance by rspectcopyrightmyass
Why? It takes the bits from the opening of 'Rosario X Vampire Capu2', the ending of 'Haruhi season 01', the opening of 'Disgaea 3', and clips from 'Slayers Next', and makes it... well, crazy. But in a good way. Watched all the way through, this piece of techno/pop just accentuates the clips being used with it, if not enhancing them ever more so.
2) Pretty fly for a Battousai by samuraichikx
Hmm... this was one that I discovered by accident some time back, and still enjoy watching to this day. Why? Well, somehow, the lyrics that're talking about white trash in suburbia today strangely fit Kenshin's profile for his 1870's character. Weird, no?
3) Escaflowne AMV - Belinda Carlisle - Heaven is a Place on Earth by bootbylicious
Now this is a tricky song to have ANYTHING put to, but the user crafted one excellent video using clips from both the series and movie versions of 'Escaflowne' to make something that is- for lack of a better term- magical.
4) >> Black Lagoon - Blow Me Away [AMV] << by Swejunk
Now this song isn't tough to put to anything, per se, but to be able to have the clips flow smoothly with the music now only in tempo but in keeping the pacing JUST RIGHT... that takes special attention from the person piecing it all together.
5) Final Fantasy VIII AMV - Celine Dion "My Heart Will Go On" by MichelleCassidy
Last, but not least, is a song that could be used over and over again for any number of couples... but this person (in my humble opinion) created something special when they gave a new breath of life to the relationship between Squall and Rinoa. Truly... beautiful.
Well, those are my picks. If y'all have any others you want to throw out there, just keep on postin'.