Here is an impromptu list:

Web design:

• Firefox 1.0 – My favourite browser
• Filezilla – Open source FTP client

General utilities:

• Textpad – Very fully featured text editor
• Jedit – A text editor for programmers. Written in Java, so the same under Windows, OS X, Linux, Unix
• 7-Zip – A compression utility, which can handle .tgz archives under Windows (very handy)
• Explorer XP – A replacement for Windows Explorer which has two great features: 1) Folder size is displayed. 2) “Create New Folder” is a button on the toolbar
• Iso Recorder – For creating images of installation CD’s for your hard disk

Music:

• CDex – Music compression / file-format changer -.wav to .mp3, and vice versa
• Audacity – A sound recorder and so much more. Very useful for recording speech
• Winamp – Music / media player. Small, but perfectly formed

Graphics:

• IrfanView – Views all images I’ve come across, plus loads of options for reducing file sizes.

I hope that you find them as useful as I do.