I'm a deep bass myself. Currently suffering from pneumonia, so I'm not exactly going to be straining to find my current deepest note (or at least, not without regretting it tremendously). I have in the past sung things like "Ol' Man River" (Show Boat), "Come Dal Ciel Precipita" (Verdi - Macbeth), "Die Frist Ist Um" (Wagner - Der Fliegende Hollander(although for this one, one could argue it's more about total range than about depth)) and many others. Since the choirs I've been a part of tend to be more aimed at a bit more modern music (musical and pop) I act there as an added baritone more often than not, when I don't it's for one or two deep notes the baritones can't touch (or of course, bass solos but we all know those are rare).