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.)