I use this binder: https://www.amazon.com/dp/B0006HV8V2/ref=cm_sw_r_cp_apa_i_F8TCDbJYMCVXS
And these sheet protectors: https://www.amazon.com/dp/B000XKW45Q/ref=cm_sw_r_cp_apa_i_I.TCDbBS43725
I was just telling a friend about my storage system yesterday.
I bought Avery mini binders and sleeve protectors. I also printed out the Playbill logo on photo paper to stick on the side, to make it more obvious what's inside 😁 they hold 22 Playbills per binder without having to worry about warping.
They only work for Playbills, as they fit perfectly in the sleeves, but they're a great [and relatively cheap] option for easy storage. It allows me to look through my Playbills without having to dig through a box. I also keep little items in the sleeves, a piece of confetti, a wristband, a button, that kind of thing.