TI-83 Plus (fully upgradable) by Texas Instruments, EUC

Easy-to-use graphing calculator; makes a great gift; graph and compare functions w/split screen options, perform data plotting & analysis; great for students or the savvy professional, allows review of multiple past entries & helps your train of thought stay on track; 160KB FLASH ROM & 24KB RAM allows students to update and add software applications (Apps); 4 AAA batteries & single CR1616/CR1620 backup battery option; well loved & in virtually mint-condition. Questions & offers always welcome.