This addon allows saving of web pages to a local subdirectory. Provides a bookmark-like interface to retrieve them - fantastic for informational pages you feel you should keep but might also want when offline. By default data is saved into your profile directory but the location can be changed.
These are from Computerworld online and describe some tweaks to about:config in Firefox. Some of these are implemented by the Fasterfox addon and I would caution people not to use the highest (fastest) tweaks as some firewall and filtering software may interpret such rapid data-fetching as an attack. In other words: if you ever see the words "Not RFC-compliant" then my advice would be NOT to enable that setting unless you know what you are doing and understand the risks to yourself and to the target server!