Reliable.com offers the Texas Instruments TI-83 Plus Graphing Calculator
(pictured), model no. TI-83PLUS, for $99.99. Pad your order over $100
and apply coupon code "VA" to cut it to $49.99
(excluding padding). With $1.48
for handling, that's the lowest total price we could find by $29. It features an upgradable operating system and software, 8-line by 16-character display, seven graph styles, and more.
Also available is the Texas Instruments TI-84 Plus Silver Edition Graphing Calculator, model no. TI-84PLUSSE, for $129.99. Coupon code "VA" drops it to $79.99. With $1.48 for handling, that's another low by $47. It stores up to 94 applications and comes with a USB cable.