Use golinks to easily manage your affiliate links in a seo-friendly way. You can even manage all of your affiliate links across as many sites as you own from this one location. Highly recommended, as you'll find that links can often change or no longer work. You won't need to go chasing down links on old pages. You won't lose all that residual traffic on broken or forgotten pages. Maybe you have a dozen different affiliate sites or pages. You'll want to install this script on site1.com. Now on all of your other sites, you'll want to use the linking format: http://www.site1.com/go/keyword-phrases for each affiliate or other link.
Have a look at the inside of the 3 files below. So few lines, yet so powerful and flexible!
; affiliate go links ; ; examples: ; keyword-phrase = "http://www.domain.com/affiliate-code" ; affiliate-one.com = "http://www.affiliate-one.com/track.php?id=ABCDEF&site=123" ; default location to send links that are not found default = "http://www.expire.biz/code/golinks/"
<?php
$request = basename($_SERVER['REQUEST_URI']);
$a = parse_ini_file('links.ini',TRUE);
if(array_key_exists($request,$a)) :
$url = $a[$request];
else :
$url = $a['default'];
endif;
header("Location: $url");
?>
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /go/
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . index.php [L]
</IfModule>