UI Scale Mod
 

Does anyone know if there is a mod that will allow you to scale individuel elements of the default UI? for example scaledown my default action bars while leaving the quest log window or AH window scaled at normal size?

Numerous mod have individual scalability. Types i can think of off the top of my head are minimap, action bars, and unit frames.

i believe you can use fluid Frames (available on this site) to move and rescale any window it can 'capture' so to speak.