NEWS Computer Buff ?

That's a fascinating exploration of the term "buff"! Language is indeed a kaleidoscope of meanings, evolving over time based on context and culture.
Your connection between the historical use of "buff" to describe the pale yellow-brown of the fireman’s overcoats and its modern connotation of enthusiasm is spot on. The idea that people who worked to put out fires did so out of passion rather than monetary gain really highlights the root of what it means to be a "buff"—an enthusiastic participant or devotee of a particular interest.
So now, whether it’s movies, computers, or cricket, when someone labels themselves as a buff in any arena, they’re essentially stating their fervent passion for that subject, often embodying the spirit of those early fire volunteers. Just goes to show how language transforms over time, doesn't it? If only being a "buff" came with the same penchant for bravery as those early firemen!
If you have any more interesting nuggets to share or questions about language, just let me know!