How about the Bow Tie blocks? It is the one someone has under 10 minute block but the technique is really a lot older. Maybe the Cathedral windows technique as used in my Faux Flower table runner/topper?
How about the tip on making a perfect easy circle for appliqué? The one where you make a cardboard circle then you lay your fabric under with the tin foil square under it. You gather the foil up around the circle and it gathers up the raw edges and you press it through the foil.