I'd just like to confirm that if I buy the Sword of the Stars - The Pit - Pilgrim DLC, that I'll be able to link it with my GOG copy of Gold Edition?

If you aren't paranoid of EA you can grap Sims 2 and ALL of it's Expansions for free
through your Origin account/ Client by entering this code: I-LOVE-THE-SIMS

http://help.ea.com/en/article/how-to-get-the-sims-2-ultimate-collection/

runs until July 31st, 2014 at 10AM PDT.

There is no such guarantee. GOG has mentioned that their DLCs work only with their games.

Wrong emphasis, I think. I'm asking if someone else's DRM-free DLC will work with GOG's base game.

I forgot to add vice versa, so I'll clarify.
There is no guarantee that you can add the DLC from another site on a GOG base game and no guarantee that you can add the DLC from GOG on a base game from another site. Proceed at your own risk.

Well, it's only 50cents so I'll give it a try.

Ooh...

On GG it's Bethesda Weekend sale. Only 50% thouhg nothing too special.

Beware though some prices differ between GG.COM and GG.UK.
E.g. Hunted - Demon Forge is 1500BLC cheaper on GG.uk than GG.com

GamersGate deals

East India Daily Deal -80%.

In addition, there is a Civilization weekend sale with deals up to -75%.

The app of the day at Amazon is Bloons TD5. This is a very very good tower defense game, highly recommended

New Weekly Humble Bundle.

1 dollar tier

Ethan: Meteor Hunter (drm-free and steam)
Finding Teddy (drm-free and steam)
Mechanic Escape (steam)

6 dollar tier

Legends of Persia (steam)
Kill the Bad Guy (steam)
Freaking Meatbags (steam)
Project Temporality (steam)

10 dollar tier

WRC 4 FIA World Rally Championship (steam)

Well, you could get Ethan: Meteor Hunter and Finding Teddy DRM-Free for less than a dollar. $1 gets you the Steam keys.

GameFly sale: http://digital.gamefly.com/?stop_mobi=once&cid=2kgf072414#!/promotion/643

Seems to only be for Australia, New Zealand, Canada, Mexico, and USA.

Meh.

In case you haven't been to the front page, GOG is having a Linux** game sale

** Where Linux == Ubuntu or Mint. If you are hipster using CentOS 7 or Fedora, you may have to do some gruntwork to get them to function. I do know that Ubuntu is headed a different direction than other LInuxes, google Wayland vs Mir for more details. However, they may not stick to this, as they recently folded in the systemd vs upstart debate.

Way Way OT:
Fedora now updates "offline", that is to say, you reboot to do updates that involve system files, and it does it during the boot sequence, similar to how Windows 7 and Mac OS X do it. Kind of shocked me to see that, apparently it's been doing it since Fedora 18. Guess I've been out of it a while.