Use a different user on each login

newuser.sh

# /root/newuser.sh
#
# Create and use a new user every time you log in.
#
# Setup:
#    ~$ nano newuser.sh
#    *paste contents of this file and save*
#    ~$ chmod +x newuser.sh
#    ~$ echo "bash newuser.sh" >> ~/.profile

# Create a new random username
newuser=$(cat /dev/urandom | tr -dc 'a-z' | fold -w 5 | head -n 1)

# Add the new user
sudo adduser --quiet --disabled-password --shell /bin/bash --gecos "User" $newuser

# Set the user password
echo "$newuser:supersupersecret" | chpasswd

# Move to the users home dir
cd /home/$newuser

# Switch to the new user
su $newuser