An erasable roller ball

Wouldn't it be great if we quilters could have a roller ball marker that comes in several colours that was easily erasable?
well we actually do have one. its called a
"Frixion erasable roller ball"
you use it like a normal roller ball but when you wish to remove the markings you simply iron it and it disappears.
In the UK they can be found in Tescos in packs of three coloures and two different sizes 0.3mm and 0.7mm.
if your fa bric is too delicate to place an iron on it then simply rub rapidy with the end stub of the pen over the ink mark and it will generate suficiant to cause the erasable action to occur.
i found this to be a great asset when using templates to guide your stitching and decorating the blocks.
price is around £6.50 per pack but i find it easier than using chalks.
annie in the uk