Here are a number of podcasts regarding software development. All of these topics are valid for Flex development. Enjoy!

Refactoring Pt. 2
http://media.libsyn.com/media/seradio/seradio-episode55-refactoring_pt2.mp3

Design By Contract
http://media.libsyn.com/media/seradio/seradio-episode51-designByContract.mp3

Architecture Patterns (Architecture Pt. 4)
http://media.libsyn.com/media/seradio/seradio-episode41-architecture_pt4.mp3

Refactoring Pt. 1
http://media.libsyn.com/media/seradio/seradio-episode46-refactoring_pt1.mp3

Dynamic Languages for Static Minds
http://media.libsyn.com/media/seradio/seradio-episode49-dynamicLanguages.mp3

Architecture Pt.3
http://media.libsyn.com/media/seradio/seradio-episode30-architecture_pt3.mp3

Architecture Pt. 2
http://media.libsyn.com/media/seradio/seradio-episode25-architecture_pt2.mp3

Development Processes Pt.1
http://media.libsyn.com/media/seradio/seradio-episode24-developmentProcesses_pt1.mp3

Architecture Pt. 1
http://media.libsyn.com/media/seradio/seradio-episode23-architecture_pt1.mp3

Service Oriented Architecture Pt.1
http://media.libsyn.com/media/seradio/seradio-episode27-soa_pt1.mp3

Error Handling
http://media.libsyn.com/media/seradio/seradio-episode7-errorhandling.mp3

Scripting Languages
http://media.libsyn.com/media/seradio/seradio-episode4-scriptingLanguages.mp3

Dependencies
http://media.libsyn.com/media/seradio/seradio-episode2-dependencies.mp3

Patterns
http://media.libsyn.com/media/seradio/seradio-episode1-patterns.mp3

Design Patterns
http://media.libsyn.com/media/ais/AiS2_copy_1.mp3

Web Services
http://media.libsyn.com/media/ais/AiS5.mp3

Unit Testing
http://media.libsyn.com/media/ais/AiS8.mp3

Advanced Unit Testing Techniques
http://media.libsyn.com/media/ais/AiS9.mp3

Database Normalization
http://media.libsyn.com/media/ais/AiS12.mp3

Abstraction
http://ais.libsyn.com/index.php?post_id=187077#

Engineering Processes
http://ais.libsyn.com/index.php?post_id=196868#

Refactoring
http://media.libsyn.com/media/ais/AiS24.mp3

Scalable Enterprise Applications
http://media.libsyn.com/media/ais/AiS35.mp3