Mario Bros. - Too many to count. I remember when I was a kid beating the game 15 times in a row in one day. It was the only game I had for a while.

Dragon Warrior- That's right. I got this game for free with my subscription to Nintendo Power. Again, too many to count. If you recall, this game is pretty lengthy and I know I beat the game at least 10 times.

Zelda: Ocarina of Time- 150 hours

Final Fantasy 10- 100 hours

Mario Kart Double Dash- 200 hours, at least

Metal Gear Solid 2- 100 hours

Bioshock- 150 hours- I've beat the game six or seven times.

Call of Duty 4- 200 hours

Gears of War 2- 250 hours and counting- This game is amazing!This game made me love everything about the Gears universe.

Mass Effect- 125 hours

Mass Effect 2- 100 hours and counting. Why more people aren't buying this game is beyond me.

Dead Space- 100 hours- This game is the second best survival horror game I've ever played. I love this game. So intense.

Resident Evil 4- 300 hours- What more can be said about this game? Ive beaten this game so many times it's ridiculous, and I've loved every single time. Absolutely everything I have ever wanted in a game. I can say this though. I've actually dug my gamecube out of the basement more than once to play this game, and I'm not a retro gamer. This is after I bought it on the Wii too. Awesome!

If we take out Punch Out and work from SNES to now, that short list alone comes to a minimum of 2 hours per day for the last 19-20 years (SNES was 1990/91 yes?)... and with your higher estimates and your "WELL over"s could easily be 3 hours per day.

Have you actually played any other games than the ones on this list?

As for my gameplay, i'm gonna count it this week as it's been a while since I totted it up... but top of the pile will remain MKWii with 350 hours. I have 3 Wii games and guesstimate 1 GC game and 1 N64 game managed over 200 hours... and a whole bunch of games between 100 and 200 hours.

Usually I get bored pretty easily so there aren't that many games I've invested a lot of time in. However, with some help from Xfire, these seem to be my most-played games:

1. Wolfenstein: Enemy Territory - Xfire ranks this at 90 hours but in my pre-Xfire era, I played this a lot. This is more than likely my most-played game. I've invested hundreds of hours in this, and I've loved almost every minute.
2. Titan Quest: Immortal Throne - I'm not sure this is right, but Xfire ranks it at 231 hours and I'm really not sure there's anything that's higher than this. The game's not that good but I keep coming back to it every now and then.
3. Civilization IV: Beyond the Sword - I bought a little more than a year ago. It sits at 147 hours, every single hour deserved.
4. Final Fantasy X - No Xfire for this one but I think it fits between #3 and #5 pretty well, sounds about right. The funny thing is that I still haven't completed it despite loving it. Heck, it's one of my favorite games ever.
5. The Elder Scrolls IV: Oblivion - 97 hours plus some ten to twenty hours for the PS3 version. The game is so flawed but occassionally I get sucked into it thanks to mods. And every time I play the game I can't help wondering how much potential the game had but Bethesda messed up with some very basic things. Still, mods make it a lot better.

Anyway, instead of playing a few games a lot, I play lots of games a little. Not quite the way it should be, in my opinion. But at least I get to experience many kinds of games.

Oh, and an honorable mention to the Dynasty Warriors series. It started with DW2, then DW3 and finally DW5. I've also played DW5: Empires, DW6, and DW6: Empires but they haven't taken so much of my time.

Civilization I-IV

You know, I actually glossed over CGI's list before, just noticed, HR at 150-200 hours?  Holy crap.  That's like what 10 playthroughs?  

You sir, are hardcore.  Most of us just loaded our game saves to change the ending, you must have played through the entire game each time :P