Well, the question is in the title.

I, personally, have 2 monitors but I use 1 for LFS.

I only have space for 1 and can't be arsed to get more, even if I had space for them.

i have one phephilion monitors !

Have one

Thats fine for me

Only one currently.
I used to have 3 at one point, but I did not use them for LFS then (SoftTH was not invented yet). But I got rid of them because two of them were CRT (blurry picture and took too much space).
Now I am planning to get 2 monitors more again..

Technically I have 4 but one is spare and unplugged. I normally run with just the central monitor though as dual screen shifts the centre of the image to where 3 inches of plastic lie, and using all three by combining two LFS sessions creates two FOV centres which is just odd, not very convincing at all.

This situation is unlikely to change until Matrox either upgrade their TripleHead2Go to cope with high vertical resolutions and refresh rates (and generally not be so biased to the TFT market), or I come up with some kind of dual graphics card solution (SLI and CrossFire too expensive to be worth the effort at the moment, time will tell if the prices drop to make it worthwhile).

technically, i also have 4, but i'm only using 2, and only one for LFS.

2x 19" wide screen LCDs
1 in use on mac
1 in use on pc

2x CRTs
1 17" blurry screen.
1 19" huge, and takes up too much room

i should sell those things.

I just have one computer monitor but I do extend my desktop to my nearby tv once in awhile to watch movies on.

Quote from glyphon :

1 19" huge, and takes up too much room

Eh, a piddly 19 incher? You live in a matchbox?

i have 2 15" and run both while playing LFS... im upgrading to 3 22" crt's next week so that should be fun woot

My MoE managing setup :P

Sat there for 24 hours. From left to right: 15" laptop - Spectator and Tracker -> 19" widescreen - Strategy (and TS on the background) -> 15" TFT - IRC


Edit: normally I only have the right two monitors though, and I play LFS only on the 19" widescreen