Grim Fandango, The Longest Journey, MI Series (I bought and enjoyed ALL of them)
This is truly a great game. Very noir.

1. Blade Runner - it's based on Dick's writing and has the visuals of my all time favourite movie. A neo noir masterpiece.
2. Sanitarium - it mixes horror and adventure games. Which is a perfect combination.
3. Grim Fandango - it has dark humour, cool story, interesting characters, good graphics - all the ingridients I love in my adventure games.

I loved adventure games and still play them today, there are still some great ones out there and companies that make them (IE Microids, the adventure company, etc).
Personally, I can never name a "Favorite" in a genre that big, I juts don't have one that I can say I like the best above any other.
I recently replayed through the Gabriel Knight series, still love it and I found the second one to really pull me in, mainly with it's mix of FMV and the interesting take on King Louie and how it was woven into the game.
Sanitarium, as mentioned already, this is one of the most gripping adventure games I've played. Th e game has this creepy atmosphere and vibe throughout that just holds you and won't let go, you constantly want to push forward to get through each new scene, b ut in the end you wish it wasn't over, you just want to play something like it, but sadly to this day I have yet to find a game that had the twisted and dreamlike quality of it.
Still Life: I love mystery games, and this one pulled me in right away from playing the demo. I knew that I was picking it up as soon as it came out, and I'm glad I did. A great gripping storyline that pushes you toward wanting to figure out who's behind it all. It's a pseudo sequel to Post Mortem, but doesn't require that you've played it. After it was over and microids folded I was so let down, as the game ends on a huge cliffhanger and everyone though that was it. Luckily Microids bounced back and a sequel is already on the way as intended and hopefully will be out in a few months.
Syberia I/II: This game is personally one of my favorites when it comes to adventure games that well, feel like adventures. The setting and characters are all so unique and fascainiting. Th e storyline was great and each locale you visit had it's own charm to it. I actually can honestly say that I liked this one a little better then The longest journey.
Dark Earth: This is a game that was VASTLY overlooked. I remember picking it up on the bargin bin at wal mart (When I was that young that's usually how I got most pc games, my dad would let me get one every week or two). It actually released at like 15 bucks, which for the game was a steal.
The game has t his great mix of Steam punk along with a late middle ages vibe to it.
It does have some action to it (fighting) but it's not too bad.
One thing I always remember though is getting home and opening up the game to put it in my computer and BAM, rigiht on the second disc is a woman with huge jugs, and when you are only 13 or so, that's awesome (it still is :p ).
Fahrenheit: To me, this was one of my favorite more recent adventure game. It took the genre in ia new direction from your usual third person point and click or first person and put it into full 3d control along with many other great innoviations.
I loved how you could truly play a scene one way and then play it again and do it differently, and it'll actually have a ripple affect later on (though not usually too drastic).
Also how you could choose at different chapters which character to play as. It made the game one of the most replayable adventure games, which is usually quite a hard thing to do in the genre, as most are linear.
I didn't mind the "twist" in the story, though many slammed it for it. My only complain really was the quick time events. This was (to my knowledge) one of the first that got the current generation of games so into it, I wish it hadn't. They just seem tedious and not only that, but they obstruct what would be some vary nice cutscenes.
However that is easily overlooked by me when it comes to it's storyline and interactions and how you can affect the game.
I can't wait to play Heavy Rain (from Quantic Dream, who made Fahrenheitt and Omikron)

Monkey Island 2, definitely.
Also, Out of This World and Flashback. Yes I know, they aren't "pure" adventures, but the story they told packing it with a timeless "action" gameplay is very special to me. Marvellous action-adventure games.

Zork Nemesis and Zork Grand Inquisitor.

I think I enjoyed Legend of Kyrandia 3 the most, followed by Day of the Tentacle, followed by the Curse of Monkey Island 3.

There are so many great adventure games and most of them are already named in this thread. The series I would like to add however is though a bit unusual is entirely deserving of note.
Penumbra: Overture
Penumbra: Black Plague
Both first person adventure horror games. Both two episodes of the same story and both equally exhilarating, challenging and surprisingly frightening. Definitely worth checking out.
[url=]http://www.penumbra-overture.com/[/url]
[url=]http://www.penumbrablackplague.com/site/[/url]

My favorite are both more recent games. Beyond Good and Evil was all around great. Im all psyched up for the sequel that's in the works! My other favorite is Primal, and its not all around great. They decided to throw in a lot of fighting, but the fighting sucks pretty bad. Still, you spend less time fighting than you do adventuring. I loved the characters and the world(s).

I keep hoping to see beyond good & evil on xbox originals, thats a game I'd buy in a shot because I've always been interested in seeing it, even after I realised you weren't playing a young friedrich nietzsche in a platforming adenture where he jumps on the heads of other philosophers he has disagreements with...
I'd be more than willing to buy it from GOG though, must have a look at the wishlist...

For me it's definately Sam and Max (
/use money with wishing well/
Sam: "I want to know what Max is thinking"
/text appears over Max' head/
Max: "."
Max: ".."
Max: "..."
Max: "!"
Sam: "Well,, that was a waste of money"
) ... nothing I've seen so far quite compares to the absurd kind of humor and the perfect animation. I don't really know why I love it so much, but there's seldom a month were I don't finish it at least once.

Just gotta be Grim Fandango, Monkey Island 3 is amazing too.

Teenagent. Polish adventure game. Ridiculously funny and my first game like that ever.
I am also very fond of the longest Journey. I loved the characters, the world and i put a lot of heart and sweat into the game so I would finish it without help (still I checked internet three or four times but only to see where should i be. just next tiny step)

Syberia 1 and 2.This is not a game.It`s a piece of art.

Monkey Island & Monkey Island 2
/thread