I've sold bits of my collection like that three times.
The first time was to go on a trip to visit some internet friends. The visit went ... very poorly, and wasn't worth getting rid of so many good things.
The second was to fund an emergency computer purchase. My second PC's CPU uh, burned up. Yes, really. I bought my current computer with that.
And the third... well, I'm in the middle of it. Building a new PC.
I've never had anyone sell my things, period. I did however experience my mother forcing me to throw out the boxes from some of my very first PC games... Gabriel Knight III, Gabriel Knight Mysteries, Tachyon The Fringe, Homeworld Game of the Year.
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