Firefox high memory consumption is one of the biggest challenges this popular, open-source project, has faced in tough browser wars, while there have been quite a few attempts to make the web-browser optimized with forks and utilities and Mozilla foundation even addressed the "memory leakage" issue with targeted efforts like MemShrink - the results were promising but nothing very exciting.
Enter "Firemin" - the free, handy, little, portable application which magically shrinked my Firefox memory usage 188 times within seconds (see comparison picture below) of launching. You simply launch the application and it eliminates all Firefox memory leaks, including the one's caused by extensions.