I want to load different versions of minecraft with mods?

I'm want to load different versions of minecraft like 1.5.2 and 1.6.4 but not have to keep switching out the mods in the folder how could I do this?

As far as I know, there's no way to get around that unless you use a launcher. But honestly it takes no effort to change your mods to don't be lazy! Haha. Hope this helps!