I have bought three things, all with knowledge from my wife:
1) The game itself. I backed Kickstarter for an amount that I have the game and all upcoming updates (Extension pass). No unneeded expenses here. I do not buy other games (except maybe once every two months some cheap App), but E-D I would have bought anyway, Kickstart or Retail...
2) Our PC was already pretty up to date (Core i7, 16GB, SSD drive, 2 screens with GraphOnBoard, since she uses it to work from home), so I only needed a graphic card. By coincidence, we won a robotic vacuum cleaner somewhere, so that went on (an Austrian version of) Craigslist, and I could buy a nice graphic card (RX270)... No extra expenses.
3) And today my X52 should arrive. No objections from my wife.
So altogether maybe EUR 150,- expenses. And she can watch the TV without me interrupting for the next several months...
Edit: The security guy just called me while I was typing this that a package was delivered for me
