If you haven't heard of a Butter Bell - you are in for a treat! If you have one, you know what I am talking about. A Butter Bell is a fantastic contraption designed to allow you to have butter fresh AND soft for spreading on toast, bagels or whatever you use it for.
Simply soften one stick of butter - not melted but just softened. Then add a 1/3 a cup of water to the larger of the two vessels. Fit the smaller vessel with the butter. Using a knife, smash it into the little cup, one stick fits perfectly. Then fit the butter "cup" into the water and you have sealed the butter with the water so it stays fresh. You need to change the water every three days or so.