In my current task, I had to use Windows not Linux :(, and of course I had to adapt to this and use my favorite software there, here are they:

Browser: Mozilla Firefox + Adblock plus + Mouse Gestures plugins
Mail: Thunderbird + Lightning + Google Calendar Plugin
Office: OpenOffice 2.3
PDF Reader: Foxit (much faster than Adobe PDF Reader)
Subversion Client: Workbench for Windows
IDE: Eclipse for Java EE for Windows
LAN Chat: BORGChat
Virtual CDs: Daemon Tools

To Be Continued…