Please note that not all of the software above are Free per se.... There is often a clause that says "Free for Personal Use"... This means you can use them at home but at office, you have to get legal software by purchasing a license... This is especially true with Security software such as "Free" Antivirus and Firewalls...
And for a really exhaustive list, you should check out sites that provide only freeware such as
www.nonags.com - do note again that the term freeware is used loosely and that some of them are free only for personal use...
Arun