During the week, I carry a small (2 inch) slip blade knife (Case, Uncle Henry, or French Laguiole). I work in a federal office building, and there are laws against anything over 2.5 inches.
When I'm not at work, for years my go-to knife was the Spyderco Delica. Great blade design, light, easy to open, decent size handle. It did everything I asked it to.
Recently, I've become somewhat enamored of the Spyderco Military. Its a similar blade design the Delica, just bigger with a much bigger handle (nice for my slightly larger than average hands), still light and easy to carry. In AL there is no size limit on folders so I've been carrying the larger Military.