I beleive some devs do not even have drm-free builds of their games, as I think gog's pitch to publishers/devs is:
You have old games not making you money, we will tweak them to run on most modern pc systems and remove the drm and we'll sell it in our store for a % or flat fee per game sale.

Which leads me to believe the gog builds could potentially be the only drm-free versions of some games.

<span class="bold">The Humble Weekly Bundle: Presented by Rock, Paper, Shotgun</span>

PWYW
Dungeons of Dredmor Complete (DRM-Free/Steam, Windows/Mac/Linux)
Audiosurf (DRM-Free/Steam, Windows)
Armageddon Empires (DRM-Free, Windows)

$1
World of Goo (Steam, Windows/Mac/Linux)

$6
Amnesia: The Dark Descent (DRM-Free/Steam, Windows/Mac/Linux)
AI War: Fleet Command+3 DLC (DRM-Free/Steam, Windows/Mac/Linux)
Teleglitch: Die More Edition+Guns and Tunes DLC (Steam, Windows/Mac/Linux)

Includes soundtracks for AI War and its 3 DLCs, Dungeons of Dredmor, Teleglitch and World of Goo.

So, according to reviews, Dungeons of Dredmor should be good enough to go for at least that tier.

From the second tier, I already have Amnesia (at HB, in fact) and I don't care about AI War. How about Teleglitch? Has anyone played it?

DoD is genuinely great! Out of the whole bundle, its only its DLCs I'm interested in, and that's still tempting me :P
Can't help with Teleglitch, though I recall it being described as top-down Quake. Or something, memory's a tad fuzzy.

TotalBiscuit talked about Teleglitch. In short, it seems to be a top-down shooter with elements of Doom and roguelike games.

Thanks, I guess at least I'll get this tier.

Oh, good. I like his videos when they don't get too long. I'll watch it later.

Teleglitch is very good. Sort of like a top-down Doom, very difficult. Crunchy, pixelated graphics. It would be a really good release for GOG if Paradox decided to move beyond Steam.

I have no idea what Rock, Paper, Shotgun is, why they're bad and, particularly, how would I be supporting them by buying this bundle.

It's a little disappointing that World of Goo isn't DRM-free. Still, I might pick it up the base tier for Dungeons of Dredmor.

I have been hoping to find Teleglitch DRM-free for so long, and here it is. Unfortunately if I want it I'm forced to also unlock an incomplete version of "AI War" and "Amnesia: The Dark Descent", a game that I will never play.

My anal retentiveness precludes me form buying the $6 tier games. This makes me so sad. :(

Am I wrong or not, by saying that it is the first time Teleglitch has been released DRM-free?

Yes, you are wrong. Teleglitch is still Steam only in this bundle.

Sorry, but Teleglitch is still Steam-only.

I also could swear it showed the drm-free icon.

Teleglitch used to be (and still is, at least for people that bought it back then, dunno about now) DRM-free on Desura, before its Steam release. It is the previous version of the game that was/is DRM-free though, the current version (Die More) is only available on Steam (Desura has provided Steam keys for that as well). On the current Humble Bundle it's the Steam-only Die More Edition.

EDIT: It's also awesome. :)