It's been a while since I posted here, might as well make this the first of the year!
My last "oops moment" happened quite recently. I was doing the DGIV 'Venus Weather' Mission. I had taken off, set up a beautiful trajectory with IMFD (perapsis before the orbit insert burn maneuver was about 300m above the center of Venus). Entered the orbit smoothly, skimming the very top of Venus' atmoshpere. I deployed the satallite and had a good look at Venus from 4M up through the eyes of the MMU dudes. I got everyone back on board and off we went, headed for home. After the ~180 day journey home, I was about 800M from earth, ready to do the last correction for the orbit insert. I was moving along at 100x time compression, but due to the lack of sleep (I had been up for nearly 20 hours), I hit the "T" key instead of the "R" key. By the time I noticed what had happened and reverted back to normal time, I was already about 80M on the other side of Earth.
Oh well, I'll just wait until I intercept Earth again, right? That's what I thought until I took a look at the Oxygen guage, which was something like this:
O
2 Tank 1: 0%
O
2 Tank 2: 17%
How it turned out: I was floating in space with all crewmembers asphyxiated.
The worst part: My last quicksave was right before the Ejection Burn from Earth.
My reaction: