I appreciate your good intentions but around here, institutions generally will not accept old computers like your G3 PowerBook. If they do accept it at all, they will hand you a nice thank you and a donation receipt and as you leave via the front door someone is at the back door putting the old computer into the Goodwill collection bin. (Goodwill handles electronics recycling for our county and maybe the entire Dallas/Fort Worth metroplex.)
Do everyone a favor and eliminate the middle man. Take it to the recycling center yourself. By the way, even in that case I would scrub the hard drive before donating it. Who knows who may get access to it when Goodwill sends it on to China or wherever for "recycling".
