Registry cure/cleaner

Hi, I am wondering if it is worth while having a registry cleaner and where i can find one that i don’t have to pay for, all the ones i have tried that say they are free scan your computer then ask you to buy the product to fix the problems it has found if any one knows of a free program please let me know
Thank-you:)

Glarysoft Registry Repair amongst others.

CrapCleaner is another.