Programming + Handiness : Hacking objects (Lin-Z, computer, tablet) to spy and steal personal data (secret,...)
Programming + Robotics : Hacking servo and bots to control them
Programming + Video gaming : Hacking multiplayer games to cheat
Mischief + Medium : Summoning evil specters anywhere
Mischief + Thanatology : Using voodoo doll to curse people (be clumsy for 24 hour, be pursued by Night Wraith or Grim Reaper)
Mischief + Romance : Blackmailing seduced sims if they are already in couple/married
Medium/Thanatology + Gemology : Putting specter/soul in gemstone to add the ability to turn into ghost or skeleton temporarily.
Acting + Mischief : Pretending friendship, it is fake but the other sims don't know it.