I was inspired to create the following feat because one of my favorite characters is a halfling fighter/barbarian, but it's impossible to find magical weapons that he can use. The campaign world we play in also has a heavy theme of racism, so most cities won't even cater to the smaller races when it comes to forging mundane weapons. Initially I also wanted to make adjustments based on the effort it would take for the smaller character to wield a larger weapon (ie - weapon focus: bastard sword would apply the +1 bonus to medium longswords wielded by small creatures, since the fighting style would be the same, weapon focus: longsword would apply the +1 bonus to medium shortswords in small hands, etc), but I couldn't think of a way to do it without having to create a huge chart listing every single weapon in the PHB and their small equivalents. Here's what I came up with instead:
Weapons of the Big Folk (General)
It is easy to come by weapons made for the taller races, but outside your peopleís settlements itís fairly difficult to find weapons made for those of your stature. Youíve learned to make the best of this and use the weapons designed for larger folk with a minimum of difficulty.
Prerequisite: STR 13, small size
Benefit: You are able to use most medium-sized weapons with which you are proficient with no penalty to attack rolls for the size difference. You may use medium-sized light weapons in one hand, but must use two hands to wield a medium-sized one-handed weapon. With the exception of the shortbow you cannot use two-handed medium-sized weapons at all, nor can you use a medium-sized heavy crossbow.
Normal: A small character takes a -2 penalty to attack rolls when wielding a weapon designed for medium characters.
Please let me know of any ways I might be able to simplify the wording of this feat, if a similar feat already exists, or just any general suggestions or feedback.