WinRar: is a tools like winzip, except on steriods.
QuickPar: is a tool verify your downloads integrity and repair corrupted posts or replace missing files if they weren't available to you.
DIVX and XVID: common codecs used to create avi files at small file size which make downloading quick and easy.
And my most favorite tool of all. http://www.binsearch.info/ this website is a simple search engine to find what has been posted in what group. It can also generate a NZB file for Forte Agent to open and collect all the parts posted for your results found in binsearch. A NZB file is a text file that has information that Agent reads and retrieves what the NZB file tells it to. Makes downloading headers almost obsolete (almost).