Old Style Future MERP. Im planning of possibly hosting one.
Nowadays Future MERP is not even a thing anymore. Space MERP is played more. And when it is Future MERP you are placed under severe restrictions to restrict your creativity to the least high levels in attempt to make "A special kind of RP". They also make your empire have 20 people at the start and able to be easily killed alongside having to develop slowly unless you are an admin in that case you can build as fast as you want. And warmongering is allowed now most of the time meaning if you start an empire someone will go up to your empire and kill you for resources and sometimes for the ego.
EDIT: Oh and then theres the most recent popular MERP, where theres no building.