Why is Half-Life: Source not eligible for Valve coupons?

Question

According to this Steam Inventory thingy(the link will show a different inventory for you, obviously), I have a 33% off coupon for Valve titles:

33% off any one title on Steam listed with Valve as the publisher.

However, Half-Life: Source does not appear in the List of applicable games for that coupon. Even though the Game Details say

Title: Half-Life: Source
Genre: Action
Developer: Valve
Publisher: Valve
Release Date: 1 Jun 2004

So how can I use this coupon to save the incredible amount of 1,65 EUR?

Answer

All coupons aren't valid until January 2nd. While I understand that HL:Source doesn't show up on the applicable games list, the coupon is valid for it.

Note that HL:Source and HL:Source Death Match are already 50% off right now, so you might as well purchase it before the sale ends as it is a better deal than the 33% coupon would give you anyways.

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What are the connections between Portal series plot and Half-Life series plot?

Question

I heard a lot of rumors about Portal series and Half-Life series plots relation but I didn't found any link.

Can you describe which relations exists between this two stories?

Answer

Aperture Science (which is the firm that developed the Portal gun) is in direct competition with Black Mesa (which is the firm for which Gordon Freeman worked) for military contracts

See the section Other facts on this link

Aperture Science and Black Mesa were bitter rivals. As seen in the Portal maps "testchmb_a_15" and "escape_02", Aperture Science employees were briefed on Black Mesa through slideshow presentations, such as one titled "Dollar$ and Sense: Competing with Black Mesa for DoD and Government-wide Acquisition Contracts"

EDIT: Here's an excellent guide on Half Life: http://members.shaw.ca/halflifestory/
Check out the timeline for an awesome detail of all events in the Half Life saga, and in the bottom a little speculation to its relation to Portal:

The date that the events of Portal take place aren't certain. We do know that GLaDOS says to Chell: "Are you trying to escape? [chuckle] Things have changed since the last time you left the building. What's going on out will make you wish you were back in here. I have an infinite capacity for knowledge, and even I'm not sure what is going on outside. All I know is I'm the only thing standing between us and them. Well, I was. Unless you have a plan for building some supercomputer parts in a big hurry, this place isn't going to be safe much longer." This implies that the game takes place during the Portal Storms or afterwards.

This site is not official but it's a great analysis IMO.

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History of Half-Life Science

Question

Are there any stories that go deeper into these the histories and purposes of locations like Black Mesa and Aperture?

Answer

The Combine Overwiki has full articles on Aperture Science and Black Mesa. These articles cover all that is canonically known about these organizations. A quick summary:

Aperture Science

• Location: Upper Michigan
• Purpose: Originally created as a shower curtain manufacturer by a successful shower curtain salesman, the company eventually evolved "into an experimental physics research institution and a bitter rival of Black Mesa" after the owner became deathly ill and brain-damaged.

Black Mesa

• Location: A city called "Black Mesa" in New Mexico
• Purpose: Helmed by the U.S. Government, Black Mesa conducts research in various theoretical and applied science fields.

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Who is the mysterious G-man in the Half-Life series?

Question

Those who played games from the Half-Life series may remember a blue-suited (may be purple) guy who was always around somewhere as if he were observing you. At the end of each episode / sequel the main character, Gordon Freeman, had some interaction with him.

The question is simple: Who is this guy?

I haven't seen a clear explanation of this.

Answer

There is not a clear explanation of this. There's not really even a good solid HINT of this. This is entirely deliberate on the part of the game developers - they haven't revealed SQUAT about this guy.

The Nihilanth was of the opinion he wasn't human, though: "You are man. He is not man."

There's a pretty good summary of everything we have at the Half-Life Wikia but I doubt you'll learn anything you didn't from playing the games (except possibly locations he shows up that you missed him).

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What order should I play the Half-life series in?

Question

For one reason or another I managed to totally miss playing any of the Half-life series. I have the time and money now to play these games that I have herd such great things about. So what are all the Half-life games that I should play? and what order should I play them in?

I am confused of where the episodes and expansions all fit in. And what they mean by "Source" versions. Are these even part of the same series? And what about Blue Shift, Lost Coast, or Opposing Force? So many games, and I don't know where or if they fit.

Are there any in the series that I should skip, or just read the plot summary for? Can someone please give me a run-down of what I should play, in order.

Answer

The must-play Half-Life games are Half-Life 1, then Half-Life 2. The expansions and spin-offs for Half-Life 1 which were not developed by Valve are quite skippable; Opposing Force, Blue Shift and Decay return to the setting and events of Half-Life 1, but portray the story through the eyes of a U.S. Marine, a security guard and two scientists, respectively.

The Source version of Half-Life is, and I quote:

a digitally remastered version of the critically acclaimed and best-selling PC game

Needless to say it's smoke and mirrors, there's absolutely no significant difference in the story.

My advice is to play the original Half-Life, Half-Life 2, and if you'd like to extend the pleasure, sequels Half-Life 2: Episode 1 and Half-Life 2: Episode 2 are quite good, but not as good as the two main games.

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What was the Vortigaunt's motivation?

Question

In Half Life the Vortigaunt's attack on sight but in Half Life 2 they help the player. Could someone please explain the motivation behind these characters.

Answer

In half-life (the first) the Vortigaunts you see are slaves, as evidenced by the green shock collars around their neck. As slaves to the Nihilanth, they are your unwilling enemies.

In the second game, the Vortigaunts encountered are free agents (effectively) and thus are not inherently on the "wrong side".

The Combine wiki has more here.

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