So I built the Jonokuchi for my office and it's working quite well.  It's a very respectable headphone amp and currently I have it driving a small pair of JVC speakers that came from a defunct mini system.  But as always, I want MOAR!  But there's a counterproductive requirement, which is that they have to be small, really small.  The JVC's are about 4" wide, 5" tall and maybe 8" deep.  My space can support something slightly larger with width only being able to be pushed about 1" larger, depth is more flexible but probably doesn't need to be.   
 
Being the non-speaker expert that I am I figured I'd ask the masses here and see what suggestions folks could come up with.  About all I've been able to manage is something on the order of the Boston Acoustics Micro 120x's or Gallo Micros.