I hate trying to spread cold butter on bread, but have always been concerned about the hygiene of just leaving a stick on the counter. Until I got a butter bell I'd just deal with the cold butter.
A friend of mine, Margaret, first introduced me to butter bells and I love mine. She was getting a few for Christmas presents for her family and I had never heard of them before, so of course had to ask. I immediately ordered 1 for myself and 1 each for my mother and mother-in-law. I have the White Classic Crock Butter Bell from ButterBell.com.
A butter bell uses water to create an airtight seal, so I use cold filtered water and replace it each morning. I can have soft butter and don't have to worry about the hygiene aspect anymore.