I was looking at Mac's memory problem - how to force it free up memory. And come across with this "100 Free Useful Mac Apps". Not all of them are free, actually. Some are sharewares and require purchase of some-sort-of-things in order to continue using them.
100 Free Useful Mac Applications (Part I)
100 Free Useful Mac Applications (Part II)
For those who like to learn about Mac's memory problem, check out this link: