Private Mode in Bash
OK I'm not sure this is perfect, but it seems to work. please report security holes.
I wanted my bash shell to have incognito\privacy mode, like my browser. So I added this line to ~/.bash_aliases
alias privatemode='export HISTFILE='
Then every time you execute the privatemode command, bash history goes no-where. I've tested it and it seems to work.. but you never know with these hack... so use on your own risk.