Web Dumper gives support to incremental downloads. Indeed, you can fetch contents by enclosing sequence numbers into brackets directly into the URL. For example:

http://www.maxprog.com/picture[12-15].jpg

will have Web Dumper to download 'picture12.jpg' to 'picture15.jpg' that is:
http://www.maxprog.com/picture12.jpg
http://www.maxprog.com/picture13.jpg
http://www.maxprog.com/picture14.jpg
http://www.maxprog.com/picture15.jpg

You can insert more sequences like in:

http://www.maxprog.com/test[1-2]/picture[001-002].jpg

resulting in the files 'picture001.jpg' and 'picture002.jpg' from the folders 'test1' and 'test2' to be downloaded from:
http://www.maxprog.com/test1/picture001.jpg
http://www.maxprog.com/test1/picture002.jpg
http://www.maxprog.com/test2/picture001.jpg
http://www.maxprog.com/test2/picture002.jpg

The possibilities are endless, you can fetch whole image libraries or any kind of file (html, movies, etc…) in a blink.