System Profiler reports a Seagate ST360020A, which was an Apple Certified Drive from around 2002 (when this eMac was released). Plus, Sys Pro says it is a 55.9GB drive, because of the whole 1000MB to 1GB thing. It shipped with a 60GB drive.

Same with the iBook, stock hard drive. Toshiba MK6026GAS. 55.89GB recognized.