It's not worth much as an ITEM--but my old Roadmaster has been very valuable as an EXPERIENCE.

I got one several years ago for free (it had been sitting in my dad's garage gathering dust.) I took it home and fixed what was wrong with it, then rode it. I tried various experiments with it (seat positions, different handlebars, derailleur adjustments, replacing the freewheel, etc.)

If you're working on a $1000 bike and you break it, you feel bad. If you're working on a $10 bike and you break it, then you improvise. So a $10 bike is less intimidating to work on, especially if you're new to bike mechanics.