This giveaway for L.A. Noire starts 18th of May and ends 26th of May.

You know where to start.

http://www.steamgifts.com/giveaway/DxXxX

D (and only D) is a digit.

No, you are not supposed to bruteforce it.

"I think I made fish too hardcore"

Okay, after I got some sleep and looked at my puzzle once again I decided it may be a little too difficult. But you can still solve it. And every day you don't people will die, starting tonight. Oh, and I will also add hints to this post.

Because today is a special occasion (the day I add the first hint) you get five cryptic hints for the price of one!

Hints

1. You start here.
2. Absolutely no pigeons are involved in this puzzle.
3. Most of the links are important because of pages they point to. But not all of them.
4. Not every hint is useful.
5. When numbers are involved, flush right.
6. This hint contains all the information you need. Seriously. It even bypasses all the puzzle steps, but two.

Solution

By looking at the source of the page you can find 4 hidden links in this message (not counting hints).

First:

Sorry

You lose

Second:

Key to winning

12 40 25 44 10

Third:

Hint

When you lose, use 0b124 with a key.

Fourth:

Negative part of the key

It is 0b20

0b is a prefix for binary constants (Hint 2). 124 is 1111100 (01111100) in binary. Exactly five 1s, just like there are five letters in a giveaway code.
"When you lose" hints to the first link. You need to take a part of it that looks like a giveaway code and apply the binary mask to it. If you are not sure about adding the leading zero hint 5 tells you to flush right.

http://pastebin.com/vANqAD7b
vANqAD7b
01111100

This leaves you with "ANqAD". But the hint tells you to use it "with a key". "The key" is in the second and third links.

First, there are five numbers. You need to add or substract them from the character codes of the letters. 20 (10100 in binary) is the "negative part", so you substract the first and the third and add the rest.

This results in 5vXmN. And there you have it.

With Hint 5 you don't need to concern yourself with getting the correct key or converting numbers to binary. Otherwise it is the same.