Media library alternatives for Drupal 6
I while ago, I wrote about the developments of the media library in Drupal 7. And while the release of Drupal 7 is only months away, there is still a high demand for a similar solution in Drupal 6. The media module for Drupal 7 aims to provide a unified field which allows you to use any files (media) avaiable in your local Drupal site or provided by remote third party services like Youtube, Flickr, etc.
So what about Drupal 6? As long as I remember we we're looking for a good solution to this issue. IMCE was never a real option as it doesn't integrate very well with the system: nodes aren't aware of any inline media provided by imce.
However, as explained in this excellent screencast video by Aaron Wall, there are recent developments which allow for some interesting Drupal 6 alternatives. These won't give you the perfect solution like the Media library but they might get you pretty close.
Filefield Sources (filefield_sources)
Extends the filefield by allowing to re-use already uploaded files or remote files. Doesn't place images inline like imagefield+insert. Has nice integration with imce.
Node Reference Embed Media Browser (nrembrowser)
Almost stable. Provides a media cck field. Tries to emulate the Drupal 7 media module. Uses node reference. Views support, JQuery UI for dialog.
Nodereference Explorer (nodereference_explorer)
Older module. Has got views support, but uses different dialog systems and doesn't support wysiwyg. Uses node reference.
Media Reference (mediareference)
Under heavy development. Provides a cck field. Views support planned, Lightbox dialog. Doesn't use node reference directly. Some of these modules use CCK's node reference as the underlying method to tie everyting together. Which seems as sensible architectural decision for Drupal 6. As Aaron explains in the video, it is important to understand the underlying technique used to store the media and the dialog system used, in order to know what works or doesn't in your projects.
At this point, I would say imce + wysiwyg + imce_wysiwyg + filefield sources is the best way to go for most situations - looking at it from an user experience point of view. However nrembrowser looks promising.