From 1.5 inch red scraps...a Bitcoin block and several little rail blocks.
From 3.5 inch scraps...Broken Dishes and anything less than a 3.5 square sewn into a strip and...
...a couple of 16 patches with stars that don't really show up all that well.
From 4.5 inch scraps...HRTs and anything less than 4.5 inch square sewn into strip and...
...a 16 inch Fractured Rail block. (Yes, I see the lower right piece is not turned correctly).
From red chunks (pieces greater than 4.5 inch but less than a FQ) some cats.
In case you haven't guessed yet red is the Rainbow Scrap Challenge color of the month.