“Wild” by Poe (just about 9 minutes long)
I’m going to 2nd Banger’s vote for NOFX’s “the Decline”.
Yes, please. 
Another vote for Jimmy Eat World’s “Goodbye Sky Harbor” and Something Korporate’s “Konstantine”.
ill throw in :
Guns N’ Roses - Estranged, Coma, November Rain, Locomotive
Led Zeppelin - Kashmir, Achilles Last Stand
“Hemispheres” by Rush, definitely. Also “Xanadu” (my personal favorite), “The Necromancer”, “Natural Science” and “The Camera Eye”.
Lotta great Yes, too, in addition to “And You and I” as mentioned by Corbomite there’s “The Revealing Science of God”, “The Gates of Delerium”, “Starship Trooper”.
My #2 favorite song would probably be “The Friends of Mr. Cairo” by Jon and Vangelis.
Then there’s “Tarkus” by ELP.
And “Fool’s Overture” by Supertramp.
Here it is, Clueless. 
Geez, all this and no Iron Maiden? I’ll have to go with Rime of the Ancient Mariner.
Virgin Steele has some good ones too including Emalaith.
I promise that I haven’t looked at the link:
DCFC is from The Bonzo Dog Band or something isn’t it?
“Freebird” live
I was right!
This song I must hear!
RealityChuck, I recommend you take a listen to DCFC. They really are amazing.
About 10% of my all-time favourites clock in at this length. In order of preference:
- Shine on your crazy diamond - Pink Floyd 25:54
- San Jacinto (live) - Peter Gabriel 8:28
- Merlin - Kayak 23:39
- Cinema show/Aisle of plenty - Genesis 12:38
- Dancing with the moonlit knight - Genesis 8:04
- Bat out of hell - Meatloaf 9:48
- American Pie - Don McLean 8:32
- Telegraph road - Dire Straits 14:15
- The ninth wave - Kate Bush 26:22
- Firth of Fifth - Genesis 9:38
- July morning - Uriah Heep 10:33
- Ripples - Genesis 8:04
- Brilliant trees - David Sylvian 8:35
Larks’ Tongues In Aspic, Part One - King Crimson (13:36)
Starless - King Crimson (12:18)
The Gumbo Variations - Frank Zappa (16:57)
The Grand Wazoo - Frank Zappa (13:19)
Heart Of The Sunrise - Yes (10:32)
Grey/Afro - Skip Spence (9:38)
In-a-godda-da-vida
Too much cawk rawk for me. Dragon Phoenix, I think you’re ‘manipulating the data’ for Shine On (admit it. it’s two songs on record)…
I’m gonna have to go with Grandaddy’s “He’s Simple, He’s Dumb, He’s the Pilot”.
This thread makes me wanna break out my old Kansas LPs. Before they got popular, they had some epic stuff, like from their album Song for America. In addition to the title track, there was also Lamplight Symphony and Incomudro - Hymn to the Atman. That’s why I didn’t take drugs in high school…I was listening to this.
“Roadie Song”
“November Rain”
That’s a classic. Dream of Mirrors is one of my favorites.
Ooh, and Cradle of Filth’s Bathory Aria is pretty sweet.
Weezer - Only In Dreams
Of course it would be “Toad” by Cream on Wheels of Fire
Sure, but both clock in at 12+, and one of the advantages of being able to burn your own CD is that I can listen to these two parts combined.
From my list, Merlin and The Ninth wave officially consist of a number of songs covering one album side, but in both cases, they have been grouped and named as a single song by the artists.