The Texas Instruments SR-50

Display: LED, 10 digits (+2 Sci. Not.)

Power: 3 AA nicads in proprietary package (BP-1A), AC adaptor

Adv. Functions: Trig, logs, hyperbolics

Memories: 1

Programming: none

Comments: I think one of the most interesting features of this calc. is the degrees/radian switch and corresponding conversion function (D/R) - depending on the position of the switch, pressing the key will convert your angle to the units selected by the switch (e.g., in degree mode, Pi then D/R will give you 180!). It's distinctive style makes this a popular model among collectors.