Put those documents on the web !! Get yourself a free account at geocities/tripod and put your documents there. Your documents will then be available for eternity ... or for whatever time your account is active :P
If you wish to share a document not encoded in plain text, and think should go to the list, then simple thing to do is to open theat file in an aaplication that created it, and save as text and then send/attach to the mail to the list. I am suggesting this since not everyone out there has a web page to host documents.
Will usually lose all formatting. Therefore, won't work with spreadsheets or PS/PDF documents. Actually ultra-simple flowing-text PDF documents will work, but not if they have math/graphics/diagrams. And have you tried reading spreadsheets saved as text? Try deciphering those looong rows of ASCII text, comma separated. A bigger pain than HTML any day. :)
Shuvam