Jagged Alliance 2 with the 1.13 mod. I can play that game all day, every day.

Looking back at the games I frequent, coupled with the games that I own on GOG.
I have to say that Masters of Magic has stayed with me the longest.
It's the one I go back to more often than Masters of Orion, or any of the RPGs that I own.

There are three main ones I can think of:

Heroes of Might and Magic 2

Master of Orion 2

Jagged Alliance 2

(I've also replayed Fallout 1+2 a dozen or so times...)

uFo Afterlight is probably the one game that you can play over and over and is a more approachable version of the original XCOM games.

Afterlight only has one campaign but that campaign can be played many times in many different ways and the story segment parts, that repeat themselves each play through, are few and short enough so that you're not wobbling the same material through most of the play through.

Also story segments tend to leave it up to you which way you're going to take the story. For instance, early in the game you come to a point where it's suggested to break peace treaty with the Reticulans but it is not necessary that you do so.


Other than that, in my library:

Ground Control II is a great RTS and offers skirmish

and

Sacrifice pretty much is a skirmish - I'm not sure if it even has a story campaign or not.

Arcanum would be my recommendation as well. On top of what arusaku has already said (well put, btw), let me elaborate by saying that I wanted to play as a smooth-talking spellcaster who would amass a mini-army of followers to do his work for him, including a meat shield, a healer, a thief, a familiar, and summoned monsters...and that's exactly what I became. The possibilities not only in plotline, but in long-term character creation are extraordinarily deep.

GothikOrk, do you like being a brute of a fighter? Or a thief? Or a diplomat? Oh hell, who am I kidding...you said yourself that you liked Fallout, so you get the idea. Arcanum is just as customizable with your character as Fallout is. The game system is decidedly different from Fallout, but its just as enjoyable.

I'd like to second Baldur's gate II and Planescape Torment, I've played each at least half a dozen times, and each playthrough can last hundreds of hours, as said.

In terms of strategy like you mentioned, Settlers II is definately a good choice. With Master of Orion I would also strongly recommend Master of Magic, the most replayable strategy game I've ever found, and in a more RPGish fantasy setting. As an alternative you might like Age of Wonders which is more modern but not quite as good :)

Also Battle Chess.

I could play Fallout and similar RPGs probably 100 times a piece.

I would have to say Duke Nukem 3D is the most replayable though. The action, attitude and fun of that game never gets old for me.

This is a tough one. I'd have to go with HOMM 3 for the atmosphere and graphics, but Total Annihilation is a great strategy game with an enormous mod base. There's a great selection of strategy games, like the Earth 21xx series and Ground Control, but those are the two that jumped into my mind first.

By the way the Baldur's Gate series, Icewind Dale series, Arcanum, and Neverwinter Nights are made, they are extremely replayble (NWN b/c of the online content of fan made mods and persistent worlds, more than its official campaign).

And nice avatar, Arusaku!

I would say Freespace 2.

With Freespace 2 you get the, well, the original Freespace campaign, and then you can go on the coomunauty website and donwload the dizains of user-made campaigns there are (with usually custom ships, custom musics, custom weapons, ...).

To do a quick list of the campaigns of professional quality (=voiced, and as good or better than the "normal" campaign). In brackets their size compared to the main campaign, which is already pretty long.

Here is a short list of the best campaigns IMO :

- The Freespace Port (100% - a transposition of the Freespace 1 main campaign with the Freespace 2 engine)
- Silent Threat Reborn (66% - a remake, much much better, of the flawed expansion campaign)
- The Procyon Insurgency (100% - a (difficult) campaign widely considered better than the original one)
- Blue Planet (200% - actually two campaigns, both of the size of the original games, which includes dizains of new ships, 2 new factions, including one new race)
- Cardinal Spear (25% - short but intense ; to be considered a a prequel to the original campaign of FS1)
- Derelict (150% - fun and long !)
- Terran Vasudan War Project (66% for what is released, the rest still under work)


So you're going to play this game for a long time !

Space Rangers (1 a 2) - space strategy RPG trading and fighting simulator... heh.

And Arcanum - It's better Fallout in "Steampunk meets high fantasy" setting.

BGs aren't replayable. That is a lie.

Total Annihilation offers near limitless replayability given the amount of content you get with it.

A couple of others to consider:

Master of Magic

King's Bounty: the Legend

Conquest of the New World Deluxe

All strategy games with robust replayability.

Neverwinter Nights.

Gotta be MOO, it's very different each game.