One way off the top of my head...

HCL Notes/Domino 8.5 Forum (includes Notes Traveler)

Subject:

Environment variables override Notes.ini values, so you could set CACHE as a global environment variable on the machines to whatever value you wanted. Since environment variable expansion works when set the value you could use %USERNAME% in the value.

So, for example, in a Windows login script you would add
set CACHE=%APPDATA%\NotesCache\cache.ndk

which would run before Notes was run and therefore override whatever value was set in Notes.ini

For a more Notes-centric approach I'll have to give it some thought.

P.S. I don't recommend hard coding C:\Temp as part of your path just because I'm paranoid and stuff

Feedback response number JMIL8N3GZC created by ~Zach Reresagengon on 10/28/2011