Soundproof headphones...?

[macroint]

I'm sure this is going to be a stupid question, but are there affordable headphones that, when worn, completely block out exterior noise?

Affordable, to me, is less than $200 for this purchase....

[Brian Skalinder]

I'm sure this is going to be a stupid question, but are there affordable headphones that, when worn, completely block out exterior noise?

Affordable, to me, is less than $200 for this purchase....

They don't block out outside sound -completely-, but they do offer substantial attenuation.  I love my ER-6s.  One benefit of the ER-6s, and an option not available on the ER-6i and the ER-4, is that I can use them with my custom-molded earplugs - simply replace the filters with the earphones.  Etymotic also offers the ER-6i and ER-4:

http://www.etymotic.com/ephp/epcomp.aspx

You should be able to find 'em all for under $200 online (not Etymotic's site), including the ER-4s.

Another option would be noise-cancelling (as opposed to the Etymotic's noise-attenuating) headphones, but I know nothing about them other than they exist.

[nickgregory]

I use the ER-6s on planes now, even without music, they block out so much of the noise it makes for a much more relaxed envrionment.

[oniontaper]

I would say er-6 too (around $100)
and for sound isolation or to reduce loud noise the er-20's ($6-$10)

[MBecker]

the shure line (e2, e3, e5, etc) all block out a substantial amount of noise (probably inline with the etymotic, but I think you'll be hard pressed to block out 100% of noise.  The key is to find the earpiece that creates the best seal within your ear.