HTTrack - HTTrack is a free (GPL, libre/free software) and easy-to-use offline browser utility.
Microlink - Extract structured data from any website
GNU Wget - GNU Wget is a free software package for retrieving files using HTTP(S) and FTP, the most...
Mailparser - Extract data from e-mails. Automate your business.
WebCopy - Cyotek WebCopy is a free tool for copying full or partial websites locally onto your harddisk for offline viewing.
Schema API - Extract structured content from the semantic web