Apache::RequestNotes provides a simple interface allowing all phases of the request cycle access to cookie or form input parameters in a consistent manner. Behind the scenes, it uses libapreq (Apache::Request) functions to parse request data and puts references to the data in pnotes( ).
Once the request is past the PerlInitHandler phase, all other phases can have access to form input and cookie data without parsing it themselves. This relieves some strain, especially when the GET or POST data is required by numerous handlers along the way.
Available from CPAN. See the module manpage for more information.