In eighth grade I went through a brief period when I was obsessed with industrial rock and metal. I am pretty sure it started when I picked up a Nine Inch Nails tape. I soon also picked up tapes by Stabbing Westward and God Lives Underwater. These were industrial rock bands with some metallic moments but were by and large more on the alternative rock side of things. This was the only real style I listened to beyond metal for awhile. It also did not last long. I soon grew tired of the music. I wanted something heavier.
It was around that time that I discovered Fear Factory. At that time, Fear Factory was combining industrial influences with metallic styles such as groove and death metal. This briefly restored my obsession with industrial music. I moved on to groups like Rammstein, Rob Zombie, and Static-X, who while not being metal bands themselves at least had that industrial metallic sound I was looking for at the time.
There are not a lot of bands that really combine industrial and metal well. Later Ministry is perhaps the best example. Incorporating thrash metal riffs with industrial rhythms, Ministry produces a disturbingly powerful wall of sound. Godflesh is the earliest band that managed to combine the two styles together. Other groups I have picked up on over the years with varying degrees of industrial elements in their metal include White Zombie, Grenouer, Daath, Skrew, Pitchshifter, Misery Loves Co., Inner Thought, Nailbomb, some Prong material, some Samael material, Strapping Young Lad, The Berserker, Anaal Nathrakh, and Zyklon.
This has long been a genre I have had some interest in. I can't really explain it. Unfortunately, there are not a lot of bands that do the style well, and even fewer that are still active. It seems to have mostly run its course. There are black metal bands now experimenting with the combination, but not many of which are very worthwhile, other than the ones mentioned above. I rarely listen to much of this anymore, but it's still a bit of a curiosity to me. Why are there not many industrial metal bands anymore?