Very indirectly and entirely personally: EVE Online.
I unintentionally became more accustomed to delayed gratification, taught myself how to make micro-optimizations in my life to clear up time, chose to re-invest my time saved investing in new skills, learned (when trying to get a job/promotion) to frame my value in terms of what fulfilling someone else's needs, learned the value of researching both how to do things AND why people recommend those methods over others, and developed a decent sense of risk:reward-informed decision-making.
as maligned as mmos are, being the gm of a guild gives you a lot of free training on how to be a manager: you have to learn how to motivate people to work together, defuse issues, deal with egos, even try to figure out ways to incentivize "unfun" activities so they get done (i.e. farming for raid materials etc.)
Not sure if you would put it on your resume, but IMHO if I was a hiring manager and I was hiring for an entry level mgmt position and somebody had "ran a successful wow guild with 50 members for 2 years" it would definitely be something I would see very positively
The local office manager was a successful wow guild leader, and he does put it into his resume and bio :) (not sure if it actually helped him land the job).
