Here are my times for this past week (September 18th through 24th)...
Centipede - 2 min.
Gyruss - 75 min.
Missile command - 4 min.
Q*bert - 180 min. in 6 sessions
Q*bert's Qubes - 16 min.
Gyruss - 17 min.
Panky the Panda - 13 min. in 3 sessions
Gyruss - 15 min.
Gyruss - 55 min.
Juice - 85 min.
Rubik's Cube - 27 min. in 2 sessions
Stockstream - 48 min.
Q*bert - 51 min. in 2 sessions
Robot wants Kitty - 30 min.
Robot wants Puppy - 52 min.
Robot wants Fishy - 89 min.
SPAR Wandercup - 6 min.
I continued to play Gyruss, but hit a brick wall in what I was able to achieve in the original arcade version, so I tried some other versions. The Colecovision one is off... the enemies are small and fast, and your shots are fast as well, but it's still hard. The Atari 2600 version is actually a bit truer to the original other than it's simplified in that the enemy formation is invisible (and unshootable). The C-64 version is what I know from back in the day, and it's quite a bit easier than the arcade original since the meteors (or asteroids?) are slower and don't come up nearly as often, and the enemy fire doesn't speed up during the game. In this version I reached the Earth, after which the game restarts from stage 01 (yes, even the stage numbers reset), only the score stays the same. After that; I also tried the Odyssey^2 port of Q*bert which is quite a bit different to the arcade. In later levels you don't get as many flying discs because there's at most 3 on screen at any one time, but to make up for that, you get many green balls.
After that, I played some variants of Q*Bert. I actually managed to beat the arcade original. It doesn't have an ending, but after finishing Level 9, Level 9 repeats, and I got that far in a 43 minute game. I also played the Q*bert variant "Juice" on the C-64 until I had the feeling I couldn't get any further Here there's a time limit instead of limiting the number of flying discs, and at some point you can't finish the level fast enough to go on. I also replayed the sequel Q*bert's Qubes, but didn't get as far as I hoped, so I only played a single game of it.
Then I briefly played "Centipede" and "Missile Command" which have been reworked as online games using "Focal Emulation". That is, I guess these are recompilations of the arcade ROM's, but they somewhat hacked the controls since both games can now be played with the mouse.
Then I tried "Panky the Panda" which is finished by now, but didn't get very far.
As for online games, I completed the first three parts of the "Robot wants..." series which is available as online games, but each sequel takes longer to finished than the previous episode. I also played an online game on the Spar homepage called "Wandercup" (wandering cup) where you play a bear collecting various food products which come scrolling at you (a bit like "Stampede") while avoiding rocks and answering questions about the products you collect. You have a time limit, but for each correctly answered question 10 seconds get added.
As for other non-eligible games, I solved Rubik's Cube some more times, and I'm getting better at it, now consistently getting times of less than 5 minutes. I also took part in Stockstream, the multiplayer stock trading "game".