If you want a fast way to get a bushel full of excellent open source applications, check into PortableApps.com. I covered this site once before from the perspective of keeping useful open source applications on a pocket USB thumb drive, and since then PortableApps has been steadily adding excellent open source applications to its free downloadable offering, including a good open source task manager, and a useful open source FTP client for those times when you need to move large files around. This is the fastest way I know of to stock up on great, OSS apps.
The free PortableApps.com Suite is a collection of open source and freeware applications including: ClamWin Portable (antivirus), Mozilla Firefox - Portable Edition (web browser), Gaim Portable (instant messaging), OpenOffice.org Portable (office suite), Sudoku Portable (puzzle game), Mozilla Sunbird - Portable Edition (calendar/task manager) and Mozilla Thunderbird - Portable Edition (email client).
In addition to the option to get all the applications in one free download, the site makes it easy to individually pick good open source applications that you're interested in. Take a look down the left rail of this page at the choices you have.
PortableApps.com's list of available, free applications is regularly updated. Recent additions include Notepad++, an excellent open source replacement for Windows' Notepad text editor, Task Coach, a good open source task manager, and FileZilla, a useful open source FTP client.
The one thing on my wish list for PortableApps.com is for it to offer Mac and Linux open source applications. Still, especially for stocking a portable drive with good open source applications, this site represents the fast track.