Our group has 5 game masters, with 3 who run more often than others. We play weekly but only face to face.
In the last year I have run Dungeon Crawl Classics, The Fantasy Trip, and Savage Worlds Agents of Oblivion. The former two using pre-written modules, the latter a X-Files style campaign.
One GM runs a sandbox fantasy D&D 3.5 campaign.
Another ran a D&D 5e campaign, and has just started running Stars Without Number.
The other guys have run Savage Worlds The Last Parsec in the past and will be running the new Deadlands release soon.