The Dark Mod
Have any of you guys seen this? It's a Thief-like stealth experience, but in a more modern engine. If you haven't played Thief, think Dishonored's stealth mechanics while actually being vulnerable in combat and stealing shit being your main goal.
It used to be a mod for Doom 3 (hence the name), but nowadays it is standalone. Best of all, it's completely free. The way it works is you download the files and install the game (actually it's just downloading the files, it's completely self-contained as far as inner workings go). Just make sure the folder is named 'darkmod'.
Then you can download missions (which are made by fans and also free) via the in-game downloader.
The mechanics are absolutely fantastic. It'll be super-hard at first, but there's a training mission included which will teach you the basics. I highly recommend this game, there's no hand-holding or other linear-structure type stuff, like minimaps or objective markers. You get the objective, you figure out yourself where to go, and try not to get caught. It's extremely fun and I highly, very highly recommend it.
Did I mention it was free, so you have absolutely no reason not to try it out? Go try it out!
I loved Thief 1,2 and 3. I didn't even KNOW this existed! I was so hype waiting for Thief 4, and now I have this. Thank you man, this is incredible.
Looked into this a bit, and I like what I'm seeing. I will definitely download and play this, when I'm tired of AC4. (And that's not going to happen for a looong time 
)
Thanks for posting!