Games you keep going back to?

Seiken Densetsu 3 :D

Anno 1701 - In my opinion the best anno ever!!!

Borderlands has probably the most hours that I've ever clocked in a single game. All the old C&C games are incredibly fun still. And Sins of a Solar Empire for pure mind-blowing strategic scale.

Portal and Portal 2. STILL epic <3

Counter-Strike Global Offensive

Psychonauts - Extremely cheap on Steam and very fun, best money I ever spent.

Quake 2 - Also incredibly cheap and, quite uniquely, the single player is more fun than the multiplayer.

Warcraft 3 - Another game with a great single player campaign. Also still has a very active multiplayer scene.

Icy Tower - Free game, always fun when you have 20 minutes to spare.

Wow you do like ME.

For me (in single player games, obviously) would be Fallout 1 and 2, Legacy of Kain Soul Reaver, Gabriel Knight 3 (i still have the retail box version, with 3 CD's)

Also, Minecraft and Terraria really sucked out the life out of me, though Terraria got worn out after a while obviously.

I dont mention multiplayer games because its kinda obvious, you're going to spend a lot of time on them.

anything on my SNES and Dreamcast, my two Favorite systems of all time, also FF 1-12 it get better every time you beat it

Half-Life 1, Opposing Force, Blue Shift, Half-Life 2, HL2:EP1, HL2:EP2...I play through the entire series at least once a year. Most interesting storyline I've ever experienced in a game. Each playthrough, I notice a new spot the G-Man shows up.

I always come back to Starcraft 1, Fallout 3, the Knights of the Old Republic 1+2, the Diablo series, the Resident Evil series, and the Hitman series.

Minecraft

Freelancer.

mario ftw!! and call of duty the first one xD..

Star trek: elite force 1 and 2, deus ex, terraria

I dont like saying it, But LoL has turned into the game i always go back. Most games only interest me through 1 playthrough or a few hours of Multi. LoL seems so natural and easy to fall back on. There are obiusly exceptions to the 1 playthrough thing. Deus Ex, Skyrim , Mafia 2 , Starcraft2, and I've surprised myself by playing a lot of BF3 Multiplayer.

Osu! Everytime they release a new beatmap for an anime I like, I always somehow come back.

Any fighting game with some sort of comedic value is pretty drawing. DBZ Budokai Tenkaichi, Mortal Kombat, and Marvel vs. Capcom 2 (because 3 is an abomination) I always seem to come back to.
I'm also a 100%-er. I can't play classic RPGs anymore because in Golden Sun, I spoke to and mind scanned every single NPC twice. If there's an RPG I haven't finished, it'll probably drag me back.
Ape Escape is a core component of my childhood and I keep wanting to play it in hopes that it will somehow be better than ever.

I'm also addicted to the Diablo series.
Any game with random map generation (Binding of Isaac, Terraria, Minecraft, Dungeons of Dredmor, Torchlight, etc.) and harsh death penalties is highly addicting for me.
The replay value has me clicking away for hours...

CoD4 ALL THE WAY!!!!
I <3 CoD4 has kept me addicted for 2 years, i play HL2, then CoD4, CoD WaW then CoD4, Mw2, then COD4, L4d2, then COD4
xD CoD is addicting

Not a single game but a series... franchise... or whatever you may wanne call it.
Egosoft's X-games.
Especially since X3 Reunion the game has been installed on my PC all the time.

Used to be the olden Final Fantasy games on PS/PS2, but as of recently I find myself in a gaming lull. Addicted to TF2 for a long long time, defected to casual gaming with Minecraft/Terraria/Dungeon Defenders. I have yet to get myself going for new games, even though I keep stocking them up. All things considered though, I suppose I'd rather go back to FF games than any other game/franchise. Or maybe Gaben's Hat-Simulator 2.

It's mass effect for me as well. (no where near as die hard as you though :O)

Final Fantasy X, I have a save file with 800+ hours on it, and I still have some save files with 50, 100 and so hours XD Kingdom Hearts 1 and 2 as well.

I've been going back to Binding of Issac a lot as well, 50 hours saved so far but that doesn't count offline.

Dota back in Warcraft III TFT still keep going back to it constantly because of the new updates and all, the mind pumping strategy to out-wit your enemies will always remain a remaining factor of why I still play Dota. Hopefully Dota 2 will solidify that bond even more :)

From time to time I keep digging out my PS2 and play some Frequency/ Amplitude. I can't get enough of those games and I really wish they would make a new and more updated game similar to it with dlc for more songs like they did with Rockband.

Dark/Demon's Souls and Final Fantasy Tactics. I go back to the Souls series (and King's Field) multiple times throughout the years. Diablo 2 gets honorable mention.