The Bohin Mechanical Pencil with ceramic leads. In fact, I have 2 of them. I keep one with just white leads in it for marking dark quilts and fabrics and the other is for the colored leads.
When using this pencil, marking is as easy as using an ink pen on paper. And the markings come out completely with just a spritz of water or washing in the machine. You can also use the eraser with the pencil or get a "CLICK" eraser (the ones with the white eraser). When marking or erasing it does not distort the fabric one bit.
The marking is bright enough to see very well but thin enough that when you quilt over it, your thread will cover the line! Also, after you mark the quilt, the lines do not "disappear" as you are working. They don't come off until you remove the lines. HOW GREAT IS THAT!
This pencil is replacing ALL of my marking tools. And trust me, I am the QUEEN OF THE MARKING TOOLS. Wanna see my collection?