Hidden Weapons: Some Ideas for D&D

So, I caught a recent thread somewhere about weird and wonderful weapons, and something that came up was that many Indian weapons had sections that could "break off" to provide a backup weapon. For example, most polearms were built with a removable dagger in the handle, presumably to allow for close-quarters fighting in a pinch. Another was the mace with a sword hidden in the handle and shaft - great if your weapon gets stuck, or you need a sharp implement fast.

It's something that isn't well represented on the tabletop, so I had a few ideas about how to implement such things:

• Polearms with hidden blades allow you to switch from a reach weapon to a close-combat dagger as a Free Action (instead of a Free Action to drop the weapon, and a move action to draw another one). Useful for swarms of small enemies who can get right on top of you.
• Maces (I'd also allow clubs, greatclubs, morningstars and most other blunt weapons) with blades hidden within the handle allow you to switch from Blunt/Bashing damage to Slashing damage as a free action once per encounter - useful if you get swallowed whole by some huge beastie and need to cut your way out. Should you roll a Critical Failure in combat, causing you to lose or damage your weapon, you can negate the failure by switching to the other weapon (though the attack is still considered a miss).

I might throw together a few more ideas shortly...