Many developers now support running programs without installing them, letting you execute software without adding anything to the system. If you're after a sort of compilation, Zero Install offers a catalog of more than 120 portable apps, covering emulators, media players, office suites, and more.
Many people prefer a conventional installation, which creates entries in the Start menu and a desktop shortcut. However, that copy becomes anchored to the computer after adding some strings to the Windows Registry and the occasional library in system folders. Under certain conditions, this behavior isn't convenient for the user, and that's when portable applications come to the rescue. Whether you run them from a hard drive or a USB stick, the software passes through the operating system almost without leaving a trace.
Running Programs Without Installing Them
Not all applications can be portable, though. Some require modules whose presence isn't guaranteed across different versions of Windows. But there are classic examples, like the NirSoft tools, whose portability is almost absolute. If you'd rather not download each program individually and prefer a repository of portable apps, you should check out Zero Install.
All you have to do is open Zero Install, update the catalog, search for the software you want, and press 'Run'. Zero Install will download a copy, set up the local cache, and run it without any installation. The catalog currently has more than 120 entries: CDBurnerXP, VLC Player, DOSBox, and GIMP are some general examples, but there are also more specialized tools like Blender, LibreOffice, VirtualDub, and PuTTY, as well as the ability to add your preferred software by providing its feed URL.
Zero Install also offers the ability to sync your software collection between computers (you can either create a free account on the site or set up your own server) and to run everything from the command line. Is the program you want not on the list? No problem! Using the publishing tools, you can add programs either by searching or by including the feed (or a catalog).
Zero Install works flawlessly and definitely deserves a place on our maintenance USB sticks. For those of us always moving around working on different computers, it's almost indispensable. It has versions for Windows, Linux, and OS X, so there's no excuse.
