i always figure i need at least 1000 yards of thread to quilt a quilt- i try to purchase cones with 2500 yards (or somewhere around there) i could probably use up a 100 yard spool of thread on a pot holder.
it is amazing how much thread it takes sometimes. connecting threads has good sales and their 500 yard spools are in a huge selection of colors- for $2. something a spool.