The Shun Ken Onion Slicer, 8" $99. If you have never tried this one in your haand, its worth the trip to WS to give it a go. Wondefullly balanced, super sharp. ergonomicallly comfortable. Wow. I have the 7 inch Santuko and LOVE it.
http://www.williams-sonoma.com/products/sku9283268/?pkey=cview-all-sale" onclick="window.open(this.href);return false;
There is a sale for the Shun Classic Utility & Paring Knife Set, $79. reg $150
It came in an email so I could not link it, but I am sure its not hard to find if the need be. I have the 6 inch utility and use it every day.