What's the longest song you've heard?

longest song i have is A Change Of Seasons by Dream Theater.. at a mere 23 minutes.

I am deprived of very long songs due to no fast internet connection and no money to buy lots of CDs.
 
Uhm
Fates Warning - A Pleasant Shade of Grey
Dream Theater - Six Degrees of Inner Turbulence

I know, they're divided into subsections, but after all they're whole songs.
 
Green Carnation here as well...

Though I have heard that Dweezil Zappa has a song he wants to release that is supposed to be around 72 minutes! I'd like to check it out, since every other l0ong song I've heard has been good.

Is there something about creating a really long song that makes artists put a lot of effort into, thereby causing it to kick ass?? It's worked for EOS, Green Carnation, and Opeth, taht's for sure....