If he were to buy a new HDD and do a clean install of OS X on it, would that get rid of everything as well? or is some information stored elsewhere?
I know he'd spend money on it before selling it and probably doesn't want to go that route but I'm curious if that will work.
now THAT'S paranoid
will it work? yes, but it is overkill.
but get this (i love making paranoid people even more skittish)
there might still be some personal information on the RAM. I mean, that's 2-4gb info. Honest to god, I read an article on engadget or somewhere relatively reputable where hackers were able to get a password or something fresh off the ram.
briefly, the method was
Step 1 - cut a hole in the box
Step 2 - put your ....... wait, different set of instructions
Step 1 - enter the password/information
Step 2 - shut down computer
Step 3 - freeze or chill the RAM (to keep it in suspended state without losing data)
Step 4 - transplant RAM to another computer or machine that read the information of the RAM that was still suspended state from the low temp
But for those people who are EXTREMELY paranoid, I'm sure that the reinstallation of 6-7gb of Leopard will fill up every nook and cranny of the 2-4gb RAM wiping it clean of prior memory.
(or does it? when was the last time your mac maxed its memory usage, so there still might be some bytes hanging out in the corner, refusing to be erased)