I take advantage of the external runtimes and the fact that folders can be nested.  My external runtimes are this
A3-H3 with each character having their own runtimes 
Animals - broken down by vending site and animal type (canine, feline, equine, fantasy, prehistoric)
Freak
Girl
Hair - and this one is broken down to DAZ Hair, RDNA Hair, PoserPros Hair and Misc Hair
Lights - again broken down by vending spot and then by types (regular, AO, IBL)
Luke-Laura - each with their own sub directory
M3-D3
Milennium Kids
Misc Characters (this for all the odd ones like the Troll)
My Characters (this is for the characters I create and has sub folders for each base (V3, A3. M3, SP3, etc)
Props - this is probably my biggest and is broken down by vending site (DAZ, RDNA, PoserPros and Renderosity - and then into categories (Vegetation, Buildings, Transportation, Environments and such)
Sixus 1 
V3-SP3, 
and now I have one for V4

As I said, some of these have multiple subfolders which are also runtimes which can be loaded just like the main folders.  I love this aspect because when I go looking for something like Traveler's Old World vegetation, then the only runtime I have to load is the RDNA Vegetation folder and I don't have to look through all the different ones from other sites.

While this kind of tree won't work for everyone, it sure makes everything easy to find for me and allows me a lot of freedom in creativity because I don't spend hours looking for things.

Hugz from Phoenix, USA

Victoria

Remember, sometimes the dragon wins. Correction: MOST times.