Well an idea I have is this.
I got about a dozen old keyboards to take apart. I did and as you know a key board has about three or four little green lights in it. So I rigged em up to a couple AA batteries and they glow! I was given a suggestion awhile ago about putting the lights in a lego town. Haven't yet but.........
If you want reallllllllyyyy small lights I suggest you get them.
I build, therefore I am.
Brave words coming from a guy called grapenuts.