Methvin | Converter 

Methvin | Converter is a freeware tool that can quickly convert all measurement formats and units into others. The application's other features include the ability to add user-defined conversions.
volume converter density converter energy converter force converter mass converter power converter pressure converter speed converter temperature converter time converter

1st Calculator 

Handy and useful expression calculator and converter with skins and lots of features
calculator converter finance expression function scientific skins math education

A Simple Unit Converter 

A customizable Program to convert Units, Converts Many Imperial Units to Metric and back again. It Converts Units in Temperature, Area,Mass, Volume, Length, Energy, Pressure and Time.
metric converter imperial converter measurement converter

AccelWare Unit Conversion Tool 

Unit Conversion Tool is a powerful, intuitive and easy-to-use utility for accurate conversion between almost every possible units of measure, from one system to another. The latest version includes more than 2200 units in 78 conversion tables.
unit conversion units measurement conversion tables unit conversion calculator unit of measure conversion unit conversion table

pmaCalc 

pmaCalc is THE replacement for your pocket calculator. it combines a scientific calculator with a programmer's calculator.
pmacalc is a expression calculator and the replacement for your pocket calculator

PG Calculator (Second Edition) 

PG Calculator is a powerfull scientific calculator and an excellent replacement for standard Windows calculator. It ofers full customizable user inteface and looks like real calculator on user desktop. PG Calculator works Algebraic and RPN modes.
calculator rpn algebra mathematic scientific skinable units