I work with a guy who collects model train equipment and has built extensive tracks/landscapes, etc. He told me he probably has around $20K invested in the hobby. Where I'm from it's routine to buy $25,000 fishing boats that are used three times per year, even if that amount represents 50% of yearly income. Of course, the Harley's that stay parked in garages 95% of the time are everywhere.... And more power to all those folks - they own things that make them happy in their own way.
On my wife's laptop, she has downloaded every picture of our kids that I've ever uploaded to picasaweb for the extended family to view - thousands & thousands of shots. They cycle on her screensaver after the laptop has been idle for a couple minutes - she sometimes just lets the screensaver go, watching the pictures, many of which document events that have already started to slip the mind.... As a life-documentation project, with some creative asides, my photography hobby has already paid for itself.
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