Features (stolen from Christophe Rhodes and others):
Mozilla and related browsers make it easy to plug arbitrary search interfaces directly into the browser. Here's a plugin file, originally created by Andreas Fuchs and modified by Zach Beane, that adds CLHS searching to your browser.
To install, copy to the searchplugins directory of your browser installation.
The default HyperSpec is hosted by Xanalys. To use a different HyperSpec installation, change the base_url in the clhs.src file.
The lookup uses the URL http://www.xach.com/clhs?q=lookup term. If your browser supports "Smart Bookmarks" or "Keyword Shortcuts" or similar, you can use that URL as a temeplate for CLHS lookups. As with the plugin file, to use a customized HyperSpec location, add a base_url value to the query.