I'm quite looking forward to it actually. I've got lots of voluntary work planned that hopefully just pays a bit of expenses (as long as I actually pay off the mortgage then I should have enough to feed, water and light the house).
As an ex fire fighter that lurks on the aviation forum, then why don't you do something like this -
Airfield Volunteer Fire Service - AVFS - Event Fire Cover - fire cover for the Shuttleworth Collection, Old Warden - fire safety training - fire engines - fire appliances - First Aid - bedfordshire
Or maybe a bit of 'first responder' stuff in the local community?
Enjoy your retirement, mate!
LJ