This is the bass tab for Fljótavík, the amazing ninth track of Sigur Rós´ Með Suð Í 
Eyrum Við Spilum Endalaust.

Let ring each note.

Intro
Bass starts at 0.19
G|--------------------------|
D|--------------------------|
A|--3---4---6---------------| x 2
E|--------------------------|

Verse (0.36)
It's the same as the Intro.

G|--------------------------|
D|--------------------------|
A|--3---4---6---------------| x 4
E|--------------------------|

Chorus (1.12)
(It's played very slowly)
G|--------------------------|
D|----------6---------------|
A|--8---4-------6-----------| x 2
E|--------------------------|

G|-----------------|
D|-----------------|
A|--4--------------|
E|-----------------|

A few seconds of silence, then piano, then Intro again.
Intro 2 (2.02)
G|--------------------------|
D|--------------------------|
A|--3---4---6---------------|
E|--------------------------|

Verse 2 (2.10)
G|--------------------------|
D|--------------------------|
A|--3---4---6---------------| x 2
E|--------------------------|

G|--------------------------|
D|--------------------------|
A|--3---4---6----886--------|
E|--------------------------|

G|--------------------------|
D|--------------------------|
A|--3---4---6---------------|
E|--------------------------|

Chorus 2 (2.47)
(It's played very slowly)
G|--------------------------|
D|----------6---------------|
A|--8---4-------6-----------| x 3
E|--------------------------|

And then a long C#.
Ending (3.38)
G|-----------|
D|-----------|
A|--4--------|
E|-----------|

Very simple song! Contact me if I made any mistake, this was my first tab.
I'm sorry for my bad english!
(Luke)