I've got one, there is a repair possible using some heat shrinking insulation tube, available from Maplin or Halfords, there are plenty on ebay & even proprietary replacementson online. I'll even have a go at fixing it.
Hi Graham - thanks for the tips. We're probably talking about the same thing - it's the bit of the cord just by the part that plugs into the laptop itself.
This part of the cable frayed some time ago and I repaired is using duct tape. We then bought a new cord which worked fine for a year, but the same thing - worse, actually - happened to the new cord so we binned that and reverted to the old one.
I suspect this is beyond repair at this point. Ideally we'd like to get a new laptop but the budget doesn't allow for that now. :-) Kinda like replacing a car because the ash trays are dirty.
Sorry for non Mac users here
The larger models, 17" and 15" have...er larger screens, & need more juice, but only if you are playing music, using photoshop, and editing video, with a flat battery that needs charging at the same time (in the dark with the keys lit up). Your choice ultimately! What size screen is it? They never come up second hand because the flex takes the jerk when you trip over the cord. I think that's why Apple changed to 'magsafe' with the later models. The fact there are replacement power supplies indicates people are keeping their Powerbooks in use - My 12" is still running despite the cycle accident.
blah blah mac, blah blah no right click, blah blah Steve Ives....