Today, many users search for a specific, elusive version: The appeal is obvious—a full-featured office suite that can run from a USB flash drive without installation, leaving no traces on the host computer. But is this quest wise, legal, or even safe?

: This is a powerful, free, and open-source office suite that can be installed on a USB drive as a truly portable app. It is compatible with all Office formats. Google Docs

If your fondness for Office 2007 is purely nostalgic, consider installing the genuine, licensed version on an old, isolated machine or inside a virtual machine—but never trust a repacked "portable" version from an unknown source.