What is (are) your favourite non-album track(s)?

I was following the forum chat about MDB's track The Sexuality of Breavement (which only seems to have been included on the U.S. release on Futurist originally) and got to wondering what are other member's favourite tracks that weren't originally released on albums. I would like to keep it to original studio tracks, so no live tracks, covers or remixes. I have a couple that spring immediately to mind, the first also being by MDB and what started me thinking about this, the superb 27 minute track The Barghest o' Whitby from the 2011 EP of the same title. Another brilliant (and long) non-album track is Moonsorrow's Tulimyrsky - a 29-minute epic folk/black metal cracker from the hour long 2008 EP(!!) of the same name.

Nearly forgot my favourite Cathedral track Schizoid Puppeteer which was originally only available on the long-deleted Rise Above label sampler compilation, Dark Passages vol 2 but is now available on the rarities disc of Cathedral's Serpent's Gold two-disc compilation.

So folks, what are your faves that weren't released on full-length albums?

Here are my top 5:

5. Converge - My Great Devastator

4. Mastodon - Death March

3. My Dying Bride - The Barghest o' Whitby

2. Meshuggah - I

1. Trivium - Drowning in the Sound

Here's a few of my favourites:

Deathspell Omega - "II" (from 2005's "Kenose" E.P.)

Pig Destroyer - "Natasha" (from 2008's "Natasha" E.P.)

Isis - "Poison Eggs" (from 1998's "The Mosquito Control" E.P.)

Nine Inch Nails - "Happiness In Slavery" (from 1992's "Broken" E.P.)

Slayer - "Haunting The Chapel" (from 1984's "Haunting The Chapel" E.P.)