The Great God Pan by Blood Ceremony.
Opeth has songs that I can listen to all the time but that is a long list to say the least. I have to honestly say with them, it would be more worthwhile to list the song that I don't listen to that much by them, then songs that I listen to all the time. To name only a few...Face of Melinda, Blackwater Park, Bleak, Lotus Eater, Under a Weeping Moon, The Lines In My Hands to name a VERY VERY VERY VERY VERY FEW.
Dirty Road by Days of the New, Fighting w/Clay by Days of the New, Shelf in the Room by Days of the New, Weapon and the Wound by Days of the New...more by them.
Voodoo Child by Hendrix.
Cocaine by Cream
The Bridge of Sighs by Robin Trower
Hellhound on my Trail-the version done by Kelly Joe Phelps
After by Ihsahn
On the Backs of Angels by Dream Theater
Wither by Dream Theater
Let's Get it On by Marvin Gaye
I Heard It Through the Grapevine by Marvin Gaye
Superstition by Stevie Wonder
That's Life by Frank Sinatra
Everybody Cares Everybody Understands and Wouldn't Mamma Be Proud by Elliot Smith and many more of his.
Into My Arms by Nick Cave(my ALL TIME FAVORITE LOVE SONG)
Quiet Desperation by Christy Moore
Stayin Alive by The Bee Gees.
One and The God That Failed by Metallica and many more
Hanger 18 and Holy Wars by Megadeth and many more
The list really could go ON AND ON AND ON AND ON and it will range through so many styles.