I found on Craigslist a seller who's selling an iMac with a "melt from the sun on the back, about the size of a loonie" for roughly $600US. It's 2.0GHz, 2GB of RAM, 320GB HDD and the buyer said I can come take a look at it, see that everything is functioning perfectly. No Applecare, though. Is this something I should go for? When iMac's hit the refurb store in Canada they are at least $1000cdn for the 20" 2.4. Is that melt something to worry about?