Simple script for Mac users who feel lack of free memory. Script automatically purges memory every 10 minutes, if there is less than 20 MB free.

Purger

#! /bin/sh

# Purging memory if there is less than 20 MB free.
# Author: Radosław Szeja
# Date: 9.12.2012

while true; do

	fm=`top -l 1 | awk '/PhysMem/ {print $10}' | sed -e 's/\([0-9]*\)\(M\)/\1/g'`;
	
	if [ $fm -lt '20' ];then 
		`purge`;
		free_mem=`top -l 1 | awk '/PhysMem/ {print $10}' | sed -e 's/\([0-9]*\)\(M\)/\1/g'`;
		let sum=$free_mem-$fm
		echo "${sum}M of memory has been purged.";
	fi
	
	sleep 10*60;
done;