Example .htaccess file with proper expiry headers set for google page speed test. Everything else is commented out and merged into the httpd.conf file for speed see: https://gist.github.com/tegansnyder/6609688

.htaccess

############################################
## uncomment these lines for CGI mode
## make sure to specify the correct cgi php binary file name
## it might be /cgi-bin/php-cgi

#    Action php5-cgi /cgi-bin/php5-cgi
#    AddHandler php5-cgi .php

    DirectoryIndex index.php

<IfModule mod_php5.c>
    php_value memory_limit 512M
    php_value max_execution_time 7200
    php_flag magic_quotes_gpc off
    php_flag session.auto_start off
    #php_flag zlib.output_compression on
    php_flag suhosin.session.cryptua off
    php_flag zend.ze1_compatibility_mode Off
</IfModule>

<IfModule mod_security.c>
    SecFilterEngine Off
    SecFilterScanPOST Off
</IfModule>

<IfModule mod_deflate.c>

############################################
## enable apache served files compression
## http://developer.yahoo.com/performance/rules.html#gzip

    # Insert filter on all content
    SetOutputFilter DEFLATE
    # Insert filter on selected content types only
    AddOutputFilterByType DEFLATE text/html text/plain text/xml text/css text/javascript

    # Netscape 4.x has some problems...
    BrowserMatch ^Mozilla/4 gzip-only-text/html

    # Netscape 4.06-4.08 have some more problems
    BrowserMatch ^Mozilla/4\.0[678] no-gzip

    # MSIE masquerades as Netscape, but it is fine
    BrowserMatch \bMSIE !no-gzip !gzip-only-text/html

    # Don't compress images
    SetEnvIfNoCase Request_URI \.(?:gif|jpe?g|png)$ no-gzip dont-vary

    # Make sure proxies don't deliver the wrong content
    Header append Vary User-Agent env=!dont-vary

</IfModule>

<IfModule mod_ssl.c>

############################################
## make HTTPS env vars available for CGI mode

    SSLOptions StdEnvVars

</IfModule>

<IfModule mod_rewrite.c>

############################################
## enable rewrites

    Options +FollowSymLinks
    RewriteEngine on

############################################
## rewrite API2 calls to api.php (by now it is REST only)

    RewriteRule ^api/rest api.php?type=rest [QSA,L]

############################################
## workaround for HTTP authorization
## in CGI environment

    RewriteRule .* - [E=HTTP_AUTHORIZATION:%{HTTP:Authorization}]

############################################
## TRACE and TRACK HTTP methods disabled to prevent XSS attacks

    RewriteCond %{REQUEST_METHOD} ^TRAC[EK]
    RewriteRule .* - [L,R=405]

############################################
## redirect for mobile user agents

    #RewriteCond %{REQUEST_URI} !^/mobiledirectoryhere/.*$
    #RewriteCond %{HTTP_USER_AGENT} "android|blackberry|ipad|iphone|ipod|iemobile|opera mobile|palmos|webos|googlebot-mobile" [NC]
    #RewriteRule ^(.*)$ /mobiledirectoryhere/ [L,R=302]

############################################
## always send 404 on missing files in these folders

    RewriteCond %{REQUEST_URI} !^/(media|skin|js)/

############################################
## never rewrite for existing files, directories and links

    RewriteCond %{REQUEST_FILENAME} !-f
    RewriteCond %{REQUEST_FILENAME} !-d
    RewriteCond %{REQUEST_FILENAME} !-l

############################################
## rewrite everything else to index.php

    RewriteRule .* index.php [L]

</IfModule>


############################################
## Prevent character encoding issues from server overrides
## If you still have problems, use the second line instead

    AddDefaultCharset Off
    #AddDefaultCharset UTF-8

<IfModule expires_module>

############################################
## Add default Expires header
## http://developer.yahoo.com/performance/rules.html#expires

   # ExpiresDefault "access plus 1 year"

ExpiresActive On
ExpiresByType image/jpg "access plus 1 month"
ExpiresByType image/jpeg "access plus 1 month"
ExpiresByType image/gif "access plus 1 month"
ExpiresByType image/png "access plus 1 month"
ExpiresByType text/css "access plus 1 week"
ExpiresByType application/pdf "access plus 1 month"
ExpiresByType text/x-javascript "access plus 1 week"
ExpiresByType application/x-shockwave-flash "access plus 1 year"
ExpiresByType image/x-icon "access plus 1 year"

</IfModule>

############################################
## By default allow all access

    Order allow,deny
    Allow from all

###########################################
## Deny access to release notes to prevent disclosure of the installed Magento version

    <Files RELEASE_NOTES.txt>
        order allow,deny
        deny from all
    </Files>

############################################
## If running in cluster environment, uncomment this
## http://developer.yahoo.com/performance/rules.html#etags

    FileETag none
#php_value upload_max_filesize 5M
#php_value post_max_size 10M