Remember when I mentioned that you can download Thou's Tyrant on last.fm? Well, turns out Thou offers free downloads of most of their stuff right on their official website. So, without further ado, click this and download some of that sludgy goodness.
With similar intentions but with a considerably smaller back catalogue, Kowloon Walled City also offers some free sludgy goodness. Though they don't have as much material under their belts as Thou, they aren't any less awesome. Because they are, too, fucking awesome.
And in other news Denovali Records also has a page with a whole bunch of free downloads, right here. So, click that thing there as well, and download some of that sludgy goodness.
Sludgy goodness for free, legally. Awesome, in my humble opinion.
But don't forget to buy the records once you realize you love them!