Have you ever tried gluing a pin made from dowel rod in a blind hole? If so you've probably encountered the nasty air pocket that forms at the bottom of the hole and makes insertion difficult. I've got a solution: tighten the dowel in a drill press chuck to create three grooves in the dowel. The grooves allow the air to escape and also hold any excess glue. Remember to spread glue into the hole first and not onto the dowel. The dowel can swell quickly from the moisture in the glue.
Good idea, particularly if you don't use dowels often enough to warrant buying a whole pile of them. I wonder how this would work, though, if your drill press has a keyless chuck?