Scientific calculator Pro with memory, date, time, currency converter, and scientific functions. It has 50 buttons and three lcd-style displays.

Scientific functions [button labels in square brackets]:

sine of x and inverted sine of x [sin] & [sin^-1]
cosine of x and inverted cosine of x [cos] & [cos^-1]
tangent of x and inverted tangent of x [tan] & [tan^-1]
arcsine of x [asin]
arcosine of x [acos]
arctan of x [atan]
x squared [x2]
square root of x [√]
x raised to the power of y [x^M] (y is first stored in the memory with [MS])
x factorial [x!]
natural logarithm of x [ln]
base-10 logarithm of x [log]
constants: E (the base of the natural logarithm) [e] & PI [π]
engineering exponent [exp]
brackets [(] & [)]
plus/minus (change sign) x [±]
Currency functions [button labels in square brackets]:
store exchange rate [¤]
convert x from currency A to currency B [$]
convert x from currency B to currency A [€]
Memory functions [button labels in square brackets]:
clear memory [MC]
store x in memory [MS] (previous memory content is deleted)
recall memory [MR]
add x to memory [M+]
subtract x from memory [M-]
see also the scientific function [x^M] above