The smallest I keep is approximately 1" square.
I do a bit of paper piecing and those small pieces come in handy. It's great to find a scrap in the bin that's already the small size I need!
Actually, I keep it all. The real scrap gets tossed into a box at the cutting board and when that's full, store it to use as stuffing.
Cathy

Less than an inch gets tossed in a box and used as cat bedding for DGD's cat and kittens. Since I started making 6 1/2" crumbs and 12 1/2" crazy crumbs, I've been saving more scraps.

I don't keep my selvedges either and they don't get cut off until I use that part of the fabric. When I buy 'yardage' I like to write on the end of the selvedge where I bought it, the date and, especially Kona Cotton, what color it is. I don't always keep it up, but I try.

SharonG/FL

Anything smaller than 1 inch square gets chopped up and put in a mesh bag for the birds to use.

beverly

Anything smaller than approximately 1.5" and 3" gets tossed. I also so not save my selvage edges.

Teresa

Here's my typical answer:

Scraps? Keep scraps??? not me... :)

I toss anything less than an inch square. I do a lot of needleturn appliquing so use a lot of fabric from the scrap bag but have to have enough for the seam allowances. I do not keep the selvage edges either.

I keep 1 1/2 strips and 3 squares. I make string quilts and follow Bonnie Hunter's projects when I have enough scraps.
Jean

I sometimes keep one inch squares and tringles if I like the fabric. I toss them into a ziplock bag. Often take it along when I know I'm going shopping for fabric so I see how new looks with some I already have. Also, they are just so pretty to look at.

I save from 2 inch size square fabric on - I have the stuff sorted in baggies or baskets by size... my 2 inch squares come in handy often -- for example for blocks being made for charity items... the other sizes I have by strip lengths comes in handy for log cabins, braided strips, etc - and really great for making binding for children's quilts... lots of color that way! As stated, the pieces you have still worth money that you already spent, so I feel it is better to find a use for it as much as you can.

As a plan I save 2 1/2 sqs., I throw strips that allow 2- 1/4" seams plus into a strip bin, they came in handy when I worked on my scrappy crumb backing that is going togeather now. I really don't think about the size, only if I might use it some time for PP; applique; who knows.
I DO save my selvages and the square up trimmings. They go into my ball. I was surprised at the sizes of some of the pieces that went in to my crumbs, great fun.
Jayne

Scraps, which I define as small offcut squares or triangles - nope, I don't keep them. I don't throw away partial strips, though.

I tried the "crumb" piecing - eh, just not for me. I didn't enjoy it. There are too many project I really want to do. I refuse to feel guilty over not doing projects that I don't enjoy.

I haven't made a hard and fast rule about it, but I guess I generally toss things that are less than 2" or 2&1/2", and the only selvages I keep are the pieces with the designer name on them, so I will know how to look for more if I ever need to. That's a great idea from SharonG. What I have gone through due to NOT writing the name of the color for kona cottons! And I'm considering keeping a crumb bag to use for stuffing, like Cathy and Sharon. I'm sure my cats would love that!

I probably save a 2" square but it also depends on the fabric and whether it had value. I use my selvedges like twine and tie up tomatoes and stuff with it.