Ujiro - Close to what i was thinking, but again, the top section of the rail system goes straight across and looks like its one piece to the top rail on the reciever.
Just found the M4 thread, this is exactly what i was thinking of:
http://img165.imageshack.us/img165/655/dsc00081oi9.jpg
I love the look of that front fore grip, but will a small lipo fit in there? What fore grip or front set is that?