Felix :
Drupal's nature of using hooks to allow functionality override by contributed modules, by the same token it is difficult to have data available between different hook implementations during the request process, specially if they are overridden. Simply we just need to have certain values available overall the system, once they are set.
Irakli:
The ability to write self-contained modules (thank you, Hooks API!) and a very flexible theming layer are two important aspects behind the power and extensibility of Drupal. The following blog post describes how to leverage this power and write "proper" modules - modules that externalize all rendering logic into TPLs, suggest default implementation but allow themers to override default TPLs if needed. Several use-cases are discussed.
Irakli:
Here is a quick introductory tutorial exposing columns in custom tables as fields in Views2. Sometimes you need to store auxiliary data outside the nodes/CCK tables, but you still want to allow Views to handle the data. Here's how to do that.
