Here are some weaponless combat rules I use IMC. I tried to hew to the philosophy of DD and its inspirational materials, keeping description minimal and the action fast. I'll let you decide if I've succeeded.
Players may, at times, either wish to or be forced to engage in combat without the benefit of weapons. Unarmed combat comes in three different varieties: brawling, grappling, and overbearing.
Brawling: Deals a point of damage per successful attack, with fighter-types adding +1 for Strength bonus if applicable [IMC fighter-types get +1 to hand-to-hand damage if STR is 15 or greater]. If the “to hit” score is ≥ 4 higher than to target number, or if a natural 20 is rolled in any case, the victim must save versus spells or be dazed for the remainder of the round and all the following round.
Grappling: May be attempted on a target by up to 6 like-sized opponents. The attackers all roll “to hit” as per normal combat. The hit dice of all attackers who successfully hit the target is totaled and as a group the attackers roll that number of six-sided dice. The target then rolls a number of six-sided dice equal to his own hit dice. If the attackers rolled the higher number, the target is pinned and helpless. If the target rolled the higher number he has thrown off his attackers, who spend the next round recovering. If the die rolls are a tie, the two factions spend the round struggling with neither side gaining the upper hand, another set of grappling rolls are made next round.
Overbear: Simply a charge ending with a grappling attempt. Success indicates the target is knocked prone and must save versus spells to avoid being pinned. If the target makes his save he scrambles to his feet next round, ready for action.
Dazed: A dazed character can only move half-speed (unless aided by an ally), cannot attack, cast spells, or do anything else requiring concentration. A penalty of -2 applies to armor class and, if alone, to his initiative roll as well. A dazed character struck in unarmed combat must roll his Constitution or under on a 20-sided die or be knocked out.
Initiative: This is diced as normal between unarmed combatants. When facing an armed opponent, including one wielding an improvised weapon, the unarmed fighter subtracts -2 from his initiative roll.
Pinned: These characters may be shackled, bound, or knocked-out at the victor's whim.
Improvised Weapons: Inflict 1-4 points of damage and include: bottles, table legs, sticks, chairs, pitchers; basically anything useable as a weapon in a pinch.
Instant Capture: Successful grappling attacks by four similarly sized opponents in the same round results in an automatic overbear and pin. (I got this directly from Gary's house rules and I really liked the way it played.)
Knocked Out: These may be dispatched in a single round by an armed opponent.