"Portable Apps" (U3-style)

I am increasingly excited about having portable apps around that I can run from my 4GB Sandisk Cruzer USB drive. I had not realized that there was a portable version of the GIMP (the Gnu Image Manipulation Program) that could be run without being installed on a PC. I see now that there is also a "portable" version of Blender, the open-source 3D modeling tool. I am working in an environment which seems to be increasingly typical, where you can't install just any software on your work PC. We also cannot bring in our personal laptops, like I could at my last job. So... the answer is "portable apps".