We had such a feature in X10, which simply involved a rubber bound box that you could stretch over all desired entities and then remove them with a single press of the DELETE key. This could be added if the community want to see this?
PC SPECS: Windows 7 Ultimate 64-bit, Intel Core i7 920 (PASSMARK:5008), NVIDIA Geforce 9600 GT GPU (PASSMARK:752) , 6GB RAM