Well, today I flashed myself a custom theme.
Liquid PSP or something like that.

Decided to go back to defaults, so I flashed these files back on:

FONT\
     ltn0.pgf
     gb3s1518.bwfon

VSH\
     resource\
          numerous files
     nodule\
          vsh.prx (deleted, as I don't think its in the default install.  Is this where i went terribly wrong? :neutral: )

KN\
     pspbtcnf.txt (or did i screw up replacing this with the default one?)

Anyways, the PSP will not start or do anything at all after replacing them.
No memory stick light, no back light, nothing.
After about 5 seconds, it turns itself back off as well.
No recovery mode either.