More about Alt-Tab Thingy
You can get the 4.0.4 version of Alt-Tab Thingy from this website. It is a free program by Nymithium Technologies and you're welcome to use it. It is classified as belonging to the System Utilities category, namely System Optimizers. Versions 4.0 and 3.4 are still the most popular ones and can be run on Windows XP/7/8/8.1. The most popular setup package name for this program is attmain.exe.