I'm always looking for easier ways to mark my quilts and I have found that this is an inexpensive , quick way to mark quilts without all the hassle. I found a tutorial on Angie's Bits n Pieces that can explain it alot better than I can.
Of course I still use my rulers and marking pens. I'm probably the reason the marking pens are still in business. No matter how dry the pen gets I have a hard time throwing them away. I have a drawer full - there might be a drop left that I might need one day.