0irc is the smallest known (IRC) Internet Relay Chat client in the world for Windows. Not only does it have a small footprint, but also contains a small set of necessary features. Features such as chat, dcc file transfers, multiple server connections and an all channel overview. 0irc is command line based with no menu, so it is meant for those who already know their way around IRC Clients. 0irc requires only 172KB for complete installation.
X-Blender is based on Blender (Popular Open Source 3D Creation Software) but contains a wrapper to allow a user to run it directly from a USB drive. With this portable 3D tool, you can model, shade, render and create all kinds of 3D graphics and effects. Best of all, it is free open source 3D creation software that can be stored on a portable USB device.
Free Unit Converter is an app or utility that allows you to convert from one unit of measurement to another. It supports up to 5000 units of measure. Some common examples include mass, distance, acceleration, volume, area, temperature, time and speed. This tool can be stored and run directly from a portable device such as a USB flash drive.
Portable Scribus is a stand alone, USB flash drive compatible version of Scribus, the popular open source desktop publishing (DTP) application. This portable desktop publishing tool allows users to create professional quality documents such as PDF files, newsletters, brochures, magazines, flyers, and books without installing software on the host computer.
As a free and open source alternative to proprietary publishing software like Adobe InDesign or the discontinued Adobe PageMaker, Portable Scribus is especially useful for designers, educators, students, and print professionals who need a powerful layout tool that can run directly from removable media.
TTCalc Portable is a nice advanced Mathematical calculator. Available in both English and Polish languages TTCalc is so simple to navigate and very easy to use. It contains hyperbolic and trigonometric functions amongst many more. The portable calculator can do conversions as well.
KeePass Password Safe is yet another great Portable Password Manager that can be run directly from a portable USB device. This application allows you to put all of your passwords in one database, which is then locked with a single password or master key disk. So you only have to remember one password or insert the key disk to unlock or gain access to the whole database.