Here's a website for crocheting helmet liners for our troops.
knottygeneration.blogspot.com/2006/10 helmet-liners-for-our-troops.html

I couldn't find it. Did it have a pattern and where to send them to? Thanks.

I typed it in too and nothing came up.(?) I originally searched this site. citizensam.org ( a site to donate quilts to wounded solders)and a couple sites below it this site to make liners was listed. (Maybe you can find it this way?) when I went to the site it had a pattern of the crochet helmet liners and this address was on the page. I should have searched the site before posting. Hope you can find it. If not let me know maybe I can find the page again. :(

If you're interested in crocheting or knitting for our military personnel, check out the Operation Toasty Toes website: http://www.operationtoastytoes.org/patterns.html

Chapter 7 is responsible for the website. Click on the Chapter link in the left sidebar. Hopefully there's a chapter near you. If not, you can always contact any of the chapters. I'm chair of Florida Chapter 19.

There seems to be a problem with this site.
But heres another one I found, searched it and seems fine.
skeinlane.com/community/documents/crochetliner.pdf

heres one for knitters-
bevscountrycottage.com/Helmet-Liners.pdf