Just to make things clear, the Portable Apps Suite runs on Windows PCs, not "Any Computer".
I have been using the Portable Apps Suite for about 6 years now. In fact I have found it so useful that I keep a copy on a "data" drive attached to my computer.
It means I can run a number of useful programmes without having to "Install" them on my C:Drive. It also means I can restore a clean copy of my Windows operating system and not have to worry about re-installing those particular programmes and their settings.

If you have them on a USB stick, and the PC you plug into is set to not "autorun",you can still start Portabl Apps manually by clicking on an icon.
One of the applications you can have on it is ClamWin, an antivirus programme. You can use it to keep the USB drive checked (I once tried using the portable version to check my PC but found it very slow on a large capacity hard drive.)
Quack!
GtD.