We have one of these Puronics things with a water softener but I have no idea if we even really need it. The quality is great and I actually enjoy softened water.
http://i.imgur.com/NPzcJoTh.jpg
http://www.puronics.com/drinking-water-systems.php
Pros:
Great water.
Entire house is filtered.
Lifetime tank warranty.
Cons:
Pricey.
They will want to do all sorts of expensive service all the time on it. Used to be every 2 years now they are saying every 8 months for a family of 4. (lol)
But... compared to new expensive refrigerator filters all the time it probably evens out (not counting the initial cost of the system.)