My thought is to implement a toolbox (brush, pencial, some color, different thicknesses, words, ...) which give's the player/s the ability to directly draw anything onto the surface of factorio. These drawings vanish after n-minutes.
Via ingame-chat or ingame-chat in addition with some third party voice-chat the occurence of a transmitter receiver problem is very high. An implementation of this could close a missing gap in communication because the receiver can just see what you're talking about.
Some advantages:
1) draw tactics in mp while attacking biter bases (text-chat too slow, voice-chat better, but still leads to missunderstandings "XY you take the three bases below the spitter base to the right side of the tree which is close to the rock under the blablabla..." "sorry what?!??!?


2) explaining an anysized build of assemblers to other players
3) support for own plannings before building
4) ...
This idea would be incomplete without giving you a PICTURE, just imagine the white surface in the picture is the surface of factorio http://3meter5.de/wp-content/uploads/20 ... t-Look.png