These cost almost nothing if you have the right size tree limbs around. (Don’t cut any limbs off trees for this, please.) Just the same, I think they are a great gift. Wood is beautiful. Tied up with a red ribbon they look very giftable.
UPDATE: I just had an idea. What if you use rounds cut from the bottom of your Christmas tree? They would have that wonderful pine smell. They would make great mementos form each year & you could use a Sharpie to mark the bottom of the coaster with the year. We always have to cut some off the bottom of our tree to make it fit anyway. And when you take down the tree you could get a few more rounds cut off before recycling the tree. I would not give these coasters away as they would be special to your family. Maybe when the kids move out you could send a few with them. Maybe the one from their first Christmas?
I would not coat them with some kind of sealer or varnish as suggested. That would get rid of the absorbancy of the wood. I like the idea of a piece of wood actually absorbing the moisture from a glass rather than just having the water bead on top & possibly roll off. You might have to keep removing the sap for a while before it’s ready to use. I guess that’s what the sealer was for, to keep the sap in.
Click title for link at Instructables. This might be a nice gift for your teens or pre-teens to make for grandpa. Or add it to a gift basket that includes a bottle of wine or liquor.