This little application–Sandboxie– create a virtual environment(think at virtualization provided by VMware) in your PC, where you can run your browser, install an applications or run an executable without to makes permanent changes on your harddisk. The programs are able to run normally because they have read access to any file in your PC, only writing procedure is intercepted by Sandboxie and redirected in a safe place on harddisk in a sandbox. No real files, folders or registries are affected by the running programs in Sandboxie. When you empty the sandbox or you shutdown the computer all the sandbox content is deleted including that temporary files from sandbox. If you run your browser sandboxed, all the cookies, browsing history are also deleted.
If you like to browse “bad” places on the Internet like porno sites, or you run an executable file acquired from untrusted sources, Sandboxie is a clever method to prevent your computer get infected with any kind of Malware.
However, you can choose what changes can be made permanent on your harddisk and what changes must be discarded.
Sandboxie supports all Windows Operating Systems 32 and 64 bits.
It can be downloaded and also has Home page here.
Note: The truth is the latest trojans can check if they run in a sandbox and kill immediately their process to hide their presence, but at least they can not infect the PC.