"Hyacinth House" by The Doors
Not only is this song catchy and then some, it contains rock's only reference to vacant lavatories. That's right, the Lizard King actually sings "I feel the bathroom is clear." Spoken like a true late stage alcoholic.
"Across the Universe" by The Beatles
Even many Beatles aficionados seem to overlook this one. Can't imagine why. More haunting than "In My Life." More chilling than "Golden Slumbers." Yeah, I said it. You wanna make something of it, little doggie?! Well I don't, so pour yourself an absinthe martini and give peace a chance.
"(Nothing But) Flowers" by Talking Heads
Not just an underrated TH song; one of the most underrated tunes in rock history. It was pushed as a single, but probably suffered from its association with Naked, their breakup album. Kind of like getting a threesome from your wife the night before she files the divorce papers.
"Not Now John" by Pink Floyd
The one highlight on their last album with Waters; the anti-Thatcher clunker The Final Cut. Should you ever find yourself stuck in a band you need to get fired from, you can't go wrong writing an album like TFC. Works better than a two week notice. Oh well, I still say "Not Now John" is a diamond in the rough. But not a blood diamond, mind you. Mr. Waters wouldn't stand for such a thing.
"2000 Man" by The Rolling Stones
Used memorably in the classic film Bottle Rocket, yet it has failed to incite the passions of rock fans. I don't have anything witty to say about this, so if you need a laugh, just picture Keith Richards trying to speak Chinese.
"A Quick One, While He's Away" by The Who
Talk about a song succeeding in spite of itself; wacky lyrics, hasty tempo shifts...all the makings of a prog rock Hindenburg. Yet I don't know of another tune in The Who's catalogue where each member shines so equally. The version I've linked is so thrilling you'll even forgive Daltrey for dressing like Pocahontas: The Burlesque Years.