PS1 Doom was probably the first game like that for me.
Star Wars arcade
I think this is unlockable in Factor 5's Rogue Squadron games.
Final Fantasy 2 (IV) is probably mine. That was like a story book come to life for me. The music was incredible and I could just leave the TV on and not do a thing, completely content to just listen.
Depends on waht you mean by reality. If you mean sense of time then probably minesweeper or solitaire, or more likely Game and Watch collection.
If you mean completely immersed in something then I have no idea.
(Yes, I know you mentioned waht you meant, but I needed to list a game for some reason rather than just posting NFI!) 
Ravenprose said:PS1 Doom was probably the first game like that for me.
The PS1 version? Was that your first exposure to the game, or did that one do something special?
gamingeek said:Star Wars arcade
...
I think this is unlockable in Factor 5's Rogue Squadron games.
Did you have an arcade near your house?
I can't remember. probably something from when I was about 5-6 and started to go to the local arcades. Maybe Pac-man or the first Wonder Boy or Ghosts and Ghoblins ... or Pooyan.
In more recent years, games I had dreams about (which I take as a sign of something affecting me deeply) were Pikmin, Eternal Darkness, Twilight Princess to name a few. Assassin's Creed II made me daydream often and for a long time about sticking secret blades into people ... especially jumping on them from above.
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Listen to Wu-Tang and watch Kung-Fu
aspro said:Did you have an arcade near your house?
Where I grew up till about the age of 14 every year across the street on the fields a funfair would set up in the summer. It had this huge arcade hall. It was actually pretty dodgy looking back, crime infested shithole. It held many happy memories of games like SF2 and Star Wars arcade and the Aliens arcade game.
One of the rides though was like two compartments on either end of a large metal bar rig. Me and my best buddy at the time went on the ride, we were in this compartment and the thing was revolving around, swinging really fast like a NASA G-force machine. And basically the door that held the compartment shut wouldn't lock and we only found out when the ride started. We basically spent 10 minutes trying to hold the door shut whilst this ride flipped us upside down and back again.
The Legend of Zelda.
Resident Evil 4.
There were a few games that made me lose my sense of reality, but none was as immersive and engulfing as when I first experienced RE "freakin" 4!
I still think no other game has had that same impact for me like that game.
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Now Playing: Golden Sun Dark Dawn, God of War Ghost of Sparta, and DKC Returns
Topic inspired by the Eurogamer podcast, can you remember the first game in which you completely lost yourself? Like when you forget the screen has a frame, and you don't feel the controller in your hands?
I guess for me it would be GUNSHIP by Microprose for the Commodore 64. I just watched a Youtube of it, and it's hard to believe now, but back when I was a kid the graphics and detail of the game fully enveloped me. As far as I was concerned I was flying an AH-64 Apache aircraft.