Math::Calc::Units is a simple calculator that keeps track of units. It only handles combinations of byte sizes and duration only, though adding any other multiplicative types is easy. Any unknown type is treated as a unique user type (with some effort to map English plurals to their singular forms). . The included 'ucalc' program prints out all of the "readable" variants of a value. For example, "3 bytes" will only produce "3 byte", but "3 byte/sec" produces the original along with "180 byte/minute", etc.
