Look here:
Two weapons selected at once. This was the effect of editing a quarterstaff's ability to say "Bow required" in "Launcher required." Since the staff now requires a bow, it can be equipped on its own but not used to attack with - doesn't show up as an available weapon. The bow, on the other hand, can be used by itself in this combination. Then it just fires arrows as usual. You can switch between the bow and the bow-staff combination on the main screen. The staff can perform as before in this combo, but I edited this one to strike at range, it made a little more sense that way. The animation was that for a swinging staff, but there was the sound of a bowstring and Minsc got hit - no flying arrow, though (I don't know what would happen if I made the staff a launcher).
See the weapon icons below.
Anyway, the point is that it's possible to use special melee or special ranged weapons in combos with bows, crossbows and slings. It makes me think of kender's hoopaks (staff + sling), or maybe firing grappling hooks out of bows or some such. Another possibility is some talismans for the weapons bar. No stand-alone use, but they could give While-Equipped bonuses when considered equipped, with the bow that is. As an alternative to quick slot items that don't do While-Equipped. A little later I tested with a crossbow and a crossbow-required throwing knife (a missile). The knife got fired all right and disappeared. Don't really know what to make of it.
