Old Mac Laptop (and iPhone) Owners -- how to fix cables!
Unsolicited endorsement follows. If such things offend you, please just ignore.
If you're like me and still use Macs and iPhones and iPads that others would consider museum pieces, then chances are excellent that you've got one or more cables that are in the process of falling apart. Not the actual connectors or in the middle, but near an end where it flexes the most. Like this:
If it's not failed yet, then I'd like to suggest Sugru. It's a moldable goo (think Silly Putty) that cures to a strong but flexible bond. After opening a packet, you've got maybe 30 minutes to shape & mold it, then just set it aside for 24 hours to cure.
I hadn't heard of it, tripped over it recently on the web, and have been pretty pleased with it so far. I've repaired all my crazy-old cables 
My only gripe is I have a lot of mag-safe connections, and the Sugru adds a little more weight to the cable so the magnetic grip doesn't seem as strong as before... but I can live with that.
Sugru isn't very cheap (approx $20 for 8 little single-use packets), but that's still way cheaper than buying new power adapters for my older Macs.
Hope this helps someone. I'm guessing there's more than one other old Apple user reading this forum who have been watching their cables slowly fall apart and wondering what to do
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