Check out the Sharpies in the office supply store. I have a fine point one that I have used. It does have a tendency 'bleed' a bit - outside edges of written lines blur - but to the best of my knowledge, it does stay forever. I can check with a quilt recipient and see how the message has held up to five years of washings.
ETA - take some light (and dark) fabrics to the store with you and see which pens you like best on both.
Last edited by NJ Quilter; 03-27-2015 at 04:50 AM.