Error dialogs allow you to highlight and copy text, for easier bug-reporting and Google searching for problems.
Open and Save dialogs can show thumbnails, and can complete filenames as you type them!
KDE 3.2 includes more spellchecking. You can spell-check what you typed into a form in Konqueror!
Konqueror can even auto-spellcheck as you type!
View contents of a ZIP file as if it were a folder with Konqueror.
Ditto for TAR archives...
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