Useful Software for Web Development

FileZilla

Open source, fast, reliable, easy-to-use FTP, FTPS and SFTP client with lots of useful features. Works with Windows, Linux, BSD, Mac OS X and more.
GIMP (GNU Image Manipulation Program)

Free yet powerful image editor that can be used for tasks such as photo retouching, image composition and image authoring. Similar to Adobe Photoshop. Works with Windows and Mac OS X.
PDFCreator

Open source program that can easily create PDFs from any Windows application.
Jaws PDF Creator

Affordable software for making high-quality PDF files. Many advanced features, plus it works on Windows and Mac.
Transmit

Affordable, easy-to-use Mac OS X FTP client with a multitude of cool and powerful features.