SoPost has become one of the best freebie providers over the past few years with the traditional approach of offering freebies one-by-one as they're released. But I only recently learned they also have a secondary site called Product Samples where they send out boxes of freebies.
It's kinda like the old PINCHme site – you create an account, then answer some questions to set up your profile, and then they'll alert you when a new batch of freebies arrives that you qualify for. It only took me 5 minutes or so to get my profile all set up.
I'll be honest, I'm not certain if this site is still heavily active or not. I researched their history and noticed they tend to offer sample boxes most frequently during the summer months, as recently as last year. So I'm hopeful if we all join today, we'll get a box of freebies sometime over the coming months!