"All Along the Watchtower" (Jimi Hendrix)

"All Along the Watchtower" is probably one of Bob Dylan's creepiest compositions.  It's involves Pinter-esque dialogue between two outcasts (the joker and the thief), set against a backdrop of apocalyptic images: howling winds, wildcats growling, and general upheaval.  At the end of the song, you're left with the feeling that the clueless patricians and their servants in the castle are about to get a rude awakening from these "two riders."
Dylan's own version on his album John Wesley Harding (1967) is good and spare.  
But Jimi Hendrix's dramatic rendition makes it easy to forget that Dylan's version existed first.  In fact, it kind of makes you forget that Hendrix didn't pen the song himself.
According to Chris Salewicz's liner notes for the now out-of-print compilation Jimi Hendrix: The Ultimate Experience (1993), Hendrix heard Dylan's version while at a party with guitarist Dave Mason of the band Traffic.  As he and Mason discussed the song, Hendrix decided on the spot that he had to record it, although he was extremely nervous about being able to do the song justice—which explains why, even though he recorded his version in January 1968, it didn't see the light of day as a single until October of that year.
Hendrix pulls out all the stops: there's layer upon layer of electric guitar—sometimes fed through a Leslie speaker, sometimes a wah-wah pedal, and other times panned between speakers through production wizardry; every solo is tasteful, strategic, and used to maximum effect.  He also plays a mean bass on the track (I actually prefer his nimble bass playing to Noel Redding's plodding style), keeping metronome time with Dave Mason, who's strumming and slashing away on the acoustic guitar.  As always, Mitch Mitchell's drums I could take or leave.  Too many sloppy fills, not enough groove.  But, thankfully, it doesn't hurt the track.
"Watchtower" (and the 1968 album Electric Ladyland on which it appears) solidified that there was more to Hendrix than electric blooze, pyrotechnic stage theatrics, and psychedelia-tinged 3-minute singles.  It cinched his lasting reputation as a priest of sound.