I have been looking to do this for sometime, and with using the nrf2401 with an ATTin85 there is only one pin left to use
This person has connected CE from the nrf to ground so that it is always in receive mode - I dont know if this works or not
I also found this... http://nerdralph.blogspot.ca/2014/01/nrf24l01-control-with-3-attiny85-pins.html which only uses 3 lines to drive a nrf24l01 from a ATtiny85.. worth a read I think.. and possibly a few experiments !!
one resistor. one diode, one cap... I dont need the LED as I am running from 3.3-3.6v Thats NOT 'loads' of external components to me