If you have a good set of kitchen knives, you need to take care of them. One of the most important parts of that is keeping them sharp.
Wustof 's 2-Stage Knife Sharpener is a very good option. It's not going to cost you an arm and a leg, either, which is a good selling point, considering you probably shelled out a fair amount of dough on your quality blades.
Priced at $US22, it has hard carbide steel sections for sharpening and fine ceramic rods for honing. To get your tools in tip-top cutting condition, you only need to swipe them through the sharpener a few times. The combination of stages is key -- you need the coarse part for cutting a new edge and the fine part for honing the edge to actually make it sharp.
Really nice knives, like Shun's Hiro Santoku or other models from Wustof, are meant to last you forever. But the only way that's going to happen is if you maintain them. So it's definitely worth it to spend 20 bucks on something that will help you do that.