I Love my **Sega Genesis **! my favorites, both of which kicked my ass so hard I eneded up owing the rental place $18 in late charges are ** Toe Jam and Earl and Phantasy Star III. **
Who’s got a cart of TJ&E?Man I’d give up the cash for that!
Also, Majong has to be the cart with the most time on it.
The singular game I have spent the most amount of time losing sleep over is actually Microsoft Solitaire.(Damn you Bill Gates I hate you) You can stop laughing now.
On the Amiga:
Emerald Mine- A sort of Diamond Mine clone, but stunning graphics
Fairie Tale Adventure- It took me a week to get through the f*cking maze in the Witch’s Forest in the upper north-east corner of the screen
Realms of Arcania- Best damned RPG ever. EVER!!!
Black Crypt- First Person dungeon crawl with gorgeous graphics.
Sigh…they don’t make 'em like that any more.
Fenris
Why hasn’t anyone mentioned Civ 3? I know I’ve stayed up late trying discover Refining just so I can find out that I have no oil sources in my territory.
Of course Persia has some just over our mutual border…
I distinctly recall losing sleep trying to figure out how to distract the stewardess in Zak McKraken and the Alien Mindbenders so I could get the oxygen tanks.
Oooo, I forgot Alpha Centauri.
I have lost sleep AND had meals go cold meal because of Civ I, Civ II, The Sims, and Princess Maker 2.
Civ in every incarnation is a given… also, there was a brief and sleepless period where the Sims and I apent many a happy midnight hour together, before I realized that my continuted successful existance depended on my banishing them from my life.
But for sheer “hey look is that dawn breaking?” distraction, GoldenEye on the N64 would be it. If any Chicagoans remember the New Year’s blizzard of 99, well, I was housebound with several friends. Over the course of three or four days, we reached that stage of total game immersion where even when you close your eyes, you’re moving endlessly forward through a FPS environment, the barrel of a Magnum just visible at the bottom of your vision, desperately hoping you’ll be the first one to get to the body armor, and knowing that Mr. Bond could be around any corner…
sigh Those were the days.
Mario 3
Mario 64
Eternal Darkness
Both Zelda’s for N64… (with the first Zelda for the N64, I stayed up all night, went to school the next day, went home sick… and instead of sleeping, I played more Zelda).
an old Nintendo games called Milan’s Secret Castle, or something like that. (We got stuck)
Wolfenstein, Diablo I and II (and additional nights for the expansion packs for each), Impossible Mission on an 8088, Xeliard, and of course, Everquest. Probably a lot more that I don’t remember; it’s all a blur by dawn.
"But the only games that have kept me up all night and didn’t have me feeling like a total ass afterwards for wasting so much time:
Suikoden II "
For me, I stayed up until like 6:30 in the morning playing that game. I’m sure I’ll do the same for Suikoden 3! Ehehhe…
"and the best game of all time, Final Fantasy Tactics. "
OH YES! Certainly among the best! 
Lunar: Eternal Blue Complete was the only other one that kept me up that LATE!
I loved Suikoden II. Two friends and I played that one together, passing the controller every so often, whenever the screen got too blurry to see.
You know you’ve been playing a game too long when you make up little songs to go with the MIDI music. And sing them aloud.
I’ve had my Chocobo Song since FFVI(III).
Riding on, a chocobo, ri-i-iding on, on a chocobo. Riding on, a chocobo, ri-i-iding on, on a chocobo-o-O!
That reminds me; I had a transcendent moment during one late-night session in the game, when I was wandering through my castle and found the “nightclub” room with the stage. This time, the two kobolds were dancing! So it was me sitting in front of a PlayStation at around 3 AM watching this fairly lengthy (around 30 seconds) animated sequence of two dog-men dancing with each other, that you have a completely random chance of ever seeing at all.
The other characters in the nightclub said it best: “…”
So I see your videogame geek factor, and raise you this: one of the tracks on the second “Cowboy Bebop” soundtrack sounds exactly like the music played in some of the towns in Suikoden II. So it always gets me feeling nostalgic for the game.
Sorry for the lengthy hijack, but I’d forgotten just how much fun that game is. And that’s not even going into the whole Iron Chef minigame!
Definately UFO Enemy Unknown, might be called X-Com in your parts of the world.
I spend alot of hours playing Sierras Hero’s Quest (adventure game, I think they changed the title later on because of some other game with the same name)
And recently, I’ve had many long nights with Dark Cloud and SSX Tricky for PS2.
Civilization 1 and 2*, and Half-Life and its online component-- TFC (oops its 3:30 AM, time to sneak into bed so the wife doesn’t catch me 
).
Alphagene: That’s why nobody has mentioned Civ 3. I can’t stand it because it seems that you are purposefully stuck in the ancient times/middle ages forever tech-wise.
The first Gabriel Knight caused me many sleepless nights and missed classes, the second one less so (but some).
I only ever played the first Civilization. I never really enjoyed it, but that didn’t stop me from sitting in front of the screen for ten hours straight on more than one occasion.
Star Control 2 kept me up a few nights, especially near the end of the game.
Finally, Tetris Plus for the PSX, in puzzle mode. Since each round lasts no more than two or three minutes you never realize time is passing until you look at your watch and it’s 4:30 AM.
–Cliffy
What, am I the only geek here who’s stayed up all night to stubbornly finish one or two boards of Chip’s Challenge?
So I’ll laugh at myself first.
Super Mario 3 and Super Mario World, especially World, kept me up till 3 and 4 am at first (to the point where a few times I had to call in “sick” to work because I hadn’t had any sleep … ); trying to get past those castles! LOL Just one more castle, then I’ll go to sleep, I’d think … yeah, right!
Recently, some of the Moraff Jongg games have kept me burning the midnight oil, trying to “beat” them, especially Ring Jongg. I’m not quite as … compelled by the games as I was a while ago fortunately. That Ring Jongg is very hard to beat (and it doesn’t help that there’s a voice in there that when there are no more moves tells you, “Oh darn!” LOL)
tarragon
Civ Call to Power
Civilization III
SimCity 3000
the Sims
Hitman 47
Max Payne
I’ve had “Holy crap! It isn’t actually 4:30 AM, is it?” Moments with all of these.