Install drupal in USBwebserver is good idea. With USbwebserver it's bundle with complete tolls like Apache, MySQL, PHP and phpMyAdmin. USBwebserver can install in computer folder, usb, cd, or in cloud such as google drive etc.
If we install in cloud base such as google drive etc..it is very useful because we can working with drupal site with other computer. That mean we can update and using drupal site anywhere and anytime.
Below is the file / folder look like - we can save it wherever we like such as in google drive etc.