Math::Big - phpMan

Math::BigFloat (3pm) - Arbitrary size floating point math package
Math::BigInt (3pm)   - Arbitrary size integer/float math package
Math::BigInt::Calc (3pm) - Pure Perl module to support Math::BigInt
Math::BigInt::CalcEmu (3pm) - Emulate low-level math with BigInt code
Math::BigInt::FastCalc (3pm) - Math::BigInt::Calc with some XS for more speed
Math::BigRat (3pm)   - Arbitrary big rational numbers