I remember an addon that did something like
- If it has information about a player: display it
- Otherwise "mark" that player
- The included binary would then read the SavedVariables file to download all data of marked players from the armory
- Repeat until your memory woes
That's just about as much as you can do, because WoW cannot access anything outside its scope (e.g. websites, binaries or files).
Also, do you trust random binaries that come with your addons? I sure as hell won't run those.
But then again the source was available IIRC and I use WoWAceUpdater...
EDIT: The addon I meant is called
Arena Enemy Talents.