Can a player ever lose her or his rating (voluntarily)? I am just curious. Is it possible for a rated player to quit his association with FIDE and start afresh, as an unrated player?
I found FIDE regulations 7.21 which state: 


  Players whose ratings drop below 1000 are listed on the next list as
  ‘delisted’. Thereafter, they are treated in the same manner as any
  other unrated player.


This sounds like a "reset" to me. 

Note that this is different to an inactive player which you become after not playing rated games for a year. However in the case of inactive players you retain your rating.

Other than this "delisting" I don't think there is a way to lose your rating.