Most developers working with Flash and Flex applications have come across Flash Tracer, a Firefox addon which makes it possible to ouput trace() commands in a panel/window in the browser window. An unvaluable tool which I'm sure many of you uses. Until recently, there hasn't been that many alternatives, but now there are:

Arthropod is an AIR application that lets you log/debug your applications by simply importing one class and using the Arthropod command log() instead of the usual trace().

Another alternative is ThunderBolt AS3 which is a logging extension letting you control the output of your messages in a more flexible way than trace(). For the output, ThunderBolt uses Firebug or the AIR application ThunderBolt AS3 Console.

Both projects are very interesting alternatives, giving you more control of how the messages are formatted. ThunderBolt is open source, hosted on Google Code.

Tags: logging, debug, flash tracer, arthropod, thunderbolt, firebug