MozillaCacheView provides a simple set of tools for exploring your Firefox browsing history. While its layout is disappointingly bland, nearly identical to its sibling ChromeCacheView, its results are unimpeachable.
The interface will instantly bore you. It's a simple row of nearly indecipherable icons, saved only by the fact that they all have mouse-over tooltips so you can figure what they do. A little bit of exploring will help you grok what each one does. In order: you can select the cache folder, open the cached item's link in your browser, copy selected cached files to a new folder, or delete selected files. The next two buttons let you filter the cache and clear the filter, and we were surprised at how well the filter worked.
You can also save items, refresh the list so you don't need to restart the program, copy items to the clipboard, view properties, and perform a search. The search option allows for a more refined process than the filter. MozillaCacheView also gives you hot keys for all its major functions, and includes several preset filters under the Options menu. Annoyingly, the program comes as a ZIP and not an executable. The program is surprisingly powerful despite the lackluster interface, and makes for an excellent lightweight way to explore your Firefox cache.