For me, this video was a great tutorial for installing Linux with the opensource software Linux Live USB creator. Because the software has a persistence option, I can even save files or install software on Linux. The persistent version of Linux allows users up to 4 GB of memory. The software also creates a virtual box on the USB, so I can also run Linux within Windows. The software is compatible with a wide range of distros and I've even managed to use it for Lubuntu Vivid Vervet 15.10 when the website said the latest version it would support is Lubuntu Vivid Vervet 15.04. The installation process took 45 minutes to an hour for me, which is much shorter than installing the OS for dual-booting. I was also saved the worry of accidentally wiping out Windows and the need to take extra precautions against this. The limitations with using Linux Live USB creator is that the OS can't be updated and the USB can not multi-boot.
Portableapps.com is the main site I use to download portable apps. It has a wide variety of programs including well-known ones such as Google Chrome, Gimp, and OpenOffice. The programs are open-source and only compatible for Windows, but Mac and Linux users can use Wine with them. There's an active community that is working on adding more portable apps to the website's collection and there's some articles about how you can make portable apps yourself. For anyone who wants to use this site, I recommend downloading the PortableApps.com Platform which displays all your portable apps from the website on this side-menu. Using the menu is easier than using the file manager to open apps, download new ones, and update your existing ones. In addition, the menu has a bar that tells you how much more space is available on the USB drive. The portable apps are fairly small and many of them can fit in a small space. The nine apps I have now in addition to the Platform take up 1.2 GB, so I could probably have at least 27 apps on one 4 GB USB drive.