FEATS
*MANYSHOT - This feat applies to all ranged attacks, not just arrows.

*TWO-WEAPON DEFENSE - If you do not use the off-hand weapon to gain extra attacks, then you do not suffer the penalties for two-weapon fighting. You would still gain the AC bonus though.

*TWO-WEAPON FIGHTING - You only incur penalties when gaining extra attacks. You may freely switch between primary and off-hand weapons in a normal progression of attacks.

For example an 11th level fighter (BAB +11/+6/+1) holding a longsword in one hand and a dagger in the other may use his longsword for the first attack, his dagger for the second (1/2 str bonus on damage), and his longsword again for the third with no two-weapon fighting penalties.