When using google to find things in the excellent Postgresql documentation, I often end up on pages showing old postgres versions. For example, googling for “postgresql create index”, the first hit is for the postgresql 8.2 docs, and I’m running 8.4 now. My co-workers made a greasemonkey script to automatically redirect to the current version, and I adapted that into a bookmarklet.
Drag this link into your address bar to to use it in your browser:
When you find yourself on a old postgres docs page, click the bookmarklet to redirect to the latest version of that page.  This should work as long as the postgres folks keep their URL naming scheme.