Web ScrapBook - A browser extension that captures the web page faithfully with highly customizable configurations.
HTTrack - HTTrack is a free (GPL, libre/free software) and easy-to-use offline browser utility.
WebCopy - Cyotek WebCopy is a free tool for copying full or partial websites locally onto your harddisk for offline viewing.
Archivarix Website Downloader - Website online downloader and Content Management System (CMS) existing site converter.
SiteSucker - SiteSucker is a Macintosh application that automatically downloads Web sites from the Internet.
A1 Website Download - Download websites to local disk for offline browsing or preserving a website soon going down.