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.