Measure Up - Converts over 600 different measurements in seven categories with web-updates.
PG Calculator (Personal Edition) - Multifunction skinable calculator for Windows
Midget - Tiny calculator with 12 variables, 32 functions, unit conversion, deg/min/sec...
Americalculator - Tape calculator w/ rule of three, interest rate, date/time calculations, etc.
WorldCalc - Calculator and currency converter with online exchange rate updates and skins.
Time Value of Money - Time Value of Money is a Finance and Loan Amortization Calculator.
SolveIT!, The Financial Calculator - A fast, easy-to-use collection of 33 financial calculators.
CalcuNote - Arithmetic calculator records and documents calculations on tapes you can edit
EngCalc (Palm) - Engineering Calculator - The best selling program for engineers now with new reference tables Evaluator
CSC Date Calculator - CSC Date Calculator counts the days before, after and between selected dates