Hi from the South of France where we are running another hard-core training course on BizTalk Server 2004.
Today's tip: BTS2004 has a very cool windows explorer extension.
To use it: (it isn't turned on by default) navigate to \program files\microsoft biztalk server 2004\developer tools and then run regsvr32 btsasmex.dll; log off and re-log on and you will magically get a BizTalk Server Assemblies icon in Windows Explorer next to your drive letters.
Clicking on any of the BizTalk Server Assemblies reflects the meta-data stored in them such as schema, orchestrations and pipelines. Even more useful is the search functionality. To use this select View-Explorer Bar-BizTalk Server Search. Using the BizTalk Server Search you can discover interdependencies between assemblies. Like all the schema that are actually referred to by maps and so on.