A fun technique to do with silk neckties is making chenille.  Use 5 or more layers of necktie fabrics over a more stable base such as heavy satin or gabardine that can then be the lining of your finished project.  Sew rows across the bias about 3/8" to 1/2" apart, then cut down the centers of the stitched rows.  I used a clothes brush to fluff the chenille, as the weave can be quite tight.  Don't use a stiffly woven fabric.  Rayon, linen, or cotton ties can also be used to great effect.