<base href="SITENAME" /> = RELATIVE LINKS THAT WORK SITEWIDE: HTML, CSS, JavaScript, PHP
<base href="SITENAME" /> = RELATIVE LINKS THAT WORK SITEWIDE
Wrote a simple howto to prevent having to rely on internal, sitewide absolute links. Only drawback is if you use subdomains and you want to preserve the subdomain path in the address bar. Really, really simple tip that saves alot of time in case need to preserve your relative links.