One possible approach is to organize your files:
- by projects (like Jonathan's suggestion: loose term for "coherent groups of files" for a common purpose)
- by packaging type, meaning:
- simple collection of files (loose and custom organization), or
- predefined structure of directories (always the same structure for every project, works well for development projects), or
- zip files (for easy synchronization / backup)
I have a zone where I put all important files/projects in compressed file in order to synchronize that directory with its mirror between my different computers (compressed files means less files to synchronize, means a quicker synchronization process. Works for backup too)