What are some alternatives?
When comparing Offline Explorer and Beyond Compare, you can also consider the following products
HTTrack - HTTrack is a free (GPL, libre/free software) and easy-to-use offline browser utility.
FileZilla - FileZilla is an FTP, or file transfer protocol, client. It lets individuals transfer single files or batches to a web server. For many years, FTP was the standard for website design. Read more about FileZilla.
WebCopy - Cyotek WebCopy is a free tool for copying full or partial websites locally onto your harddisk for offline viewing.
WinMerge - WinMerge is an open source differencing and merging tool for Windows.
Wget - GNU Wget is a free software package for retrieving files using HTTP(S) and FTP, the most...
Meld - What is Meld? Meld is a visual diff and merge tool targeted at developers.