Kalkulator 

Advanced Sci/Eng calculator. Expression evaluation, 18 digits precision, variables, 100 functions, graphs, unit conversion, interpolation, polynomial regression, linear algebra, systems of linear, nonlinear and differential equations, optimization.
calculator math science engineering numerical methods statistics differential equations linear algebra nonlinear equations interpolation

Mr. Matt 

Addictive puzzle game, similar to to Boulderdash; teen to adult; no gore or violence. Trial version includes 10 games (49 levels), registration offers over 500 extra games (2500 levels) and game editor. Sound effects, worldwide Hall of Champions.
game mr. matt puzzle mind games boulderdash

Midget 

Tiny but smart calculator: just type in any expression, like "2+3/7.1-3sqr 5", and hit Enter; then modify it and evaluate again without re-entering everything. 18-digit precision, 30 functions, 12 memories, fractions, deg/min/sec, more!
math science engineering calculator expressions midget