Here is a pitch shifter written in 1 line of bash. You may need to play with the silence bit of the code if it is too sensitive, or not sensitive enough. Also, change values in the e variable for different effects.
e="norm pitch 1000";echo q exits.;f=`mktemp`;while ! read -n1 -t.5 ;do rec -qtwav $f silence 0 1 .5 1%&&play -q $f $e;done;\rm $f