In Brazil there is something similar to the US called passe livre (literal translation would be "free pass").
There is a central database where all brazilian airlines register their crew members (pilots and flight attendants). Once you are in the system you can issue tickets on any domestic flight on any airline and board as long as there is an available seat. Jumpseat is upon captain's discretion and/or each company's policy.
There are a few rules:
You must issue a ticket or make a reservation via the system
You must be dressing your full airline uniform and airline ID in order to board the aircraft.
Maximum 5 free pass passengers onboard per flight.
It helps a lot pilots and flight attendants who live in cities other than their contractual bases.
This benefit conquered by our union 2 years ago and it works quite well nowadays.