anything that I can make either a strip of at least 1" wide, or a 2" block is a keeper....smaller than that is tossed.

I save scraps that are 1 1/2 inches and what ever is left I save it in a bag and use it for cat beds or suffing pillows.

I toss anything under 1 1/2" square.

Those I can cut at least 1 1/2" squares and 1" strips

Anything over an inch square. BUT let me explain here, I have a friend who does mini piecing, so she will use things as small as 3/4" cut (finishing 1/4") so all my scraps (anything under about 5" square) goes into a bag and she gets them several times a year. Its really neat to see what she uses the small pieces to create.

Please go to quiltville.com. She is the Scrap Queen! Read her ideas for saving different size scraps.

anything bigger than lint.

I think I'm with ptquilts. I save everything. I recently made an applique quilt with kittens and puppies and hated buying a FQ to make the inner ears of 3-4 blocks. I needed maybe a 3 x 3 inch square of fabric. The rest is in my stash--a win win I guess.
Sue

It all depends on what the person wants to accomplish with them. I save everything that is big enough get applique from and larger for blocks and strips