My santoku is stuck at the sharpener's shop until they reopen on Wednesday, so I'm stuck cooking this weekend without it. I didn't realize how much I missed it until I got around to doing a couple of things it does well: lettuce and onions. I can do them with my chef's knife, but I definitely feel a greater degree of precision for those two tasks with the santoku.
Also, strangely enough, I have discovered that my best tomato knife is actually a vintage Chicago Cutlery boning knife. Nothing about it says quality--mass produced, stamped blade--but since I had my sharpener go to work on it a couple of weeks ago, it has become my lunchtime knife. It does a decent job (for a non-serrated knife, anyways) of halving focaccia rolls, a good job of handling red peppers, and an unbelievable job of slicing tomatoes. I also checked to see how good of a job it did at a julienne on those peppers, and it did great there too. It's not at all what the knife was intended for, but I think I have a new favorite (and an inexpensive, easily replaceable one at that) for precision work, and sammiches too.
Before I quit my job as the Sous Chef for a very nice hotel/restaurant/convention center I used a wide variety of knives. Now, I still take a roll to work but I really only need four of five knives: a serrated bread knife (I usually take a Kershaw Kai Pure Komachi to work- very sharp yet cheap enough to let the bread guy use it every day), a Messermeister birds-beak peeling knife, an 8" Wustof French knife, a 7" granton-edged Henckels santuko, and a 6" forged utility knife. Occasionally I use others; we serve prime rib on weekends so I use my Forschner Fibrox 12" granton-edged slicer for that. And since I'm a knife nut I usually have three or four santukos and several French knives in my roll (Kershaw Kai Wasabi & Shun santokus, Shun Chef knives), plus an assortment of other Shuns.
