Sometimes I do. Mostly I leave them buried in the seam allowances of my quilts. My mom, on the other hand, saves hers and actually uses them. Look at this adorable little mini quilt:
The half square triangles finish at 2", so I'm guessing with the border it's 16"x18" The bonus triangles and the border fabric came from this project:
The half square triangles in this one are even tinier, finishing at 1"
Think I should start actually cutting those triangles off?