The Perl 5 module Data::Taxi is a data serializer with several handy features:
Taint aware
  The data to be serialized does not have to be trusted.  None of
  the input data is executed.
Human readable
  Data::Taxi produces a human-readable string that simplifies checking
  the output of objects.
XML-ish
  Without begin fully XML compliant, Data::Taxi produces a block of
  XML-ish data that could probably be read in by other XML parsers.