I would have never expected to talk about this on a watch forum... did I mention how much I like this place? :)
It's been almost all PC gaming for me, and my "preferred brand" has changed over the years. When I first started it was adventure games, then the early FPS stuff (id software and 3D Realms), then the later FPS stuff (Valve). Throw in a little Elder Scrolls series (Bethesda), Fallout (Interplay, then Bethesda), and anything that Bioware has made. I should stop.
Anyways, my "Heuer of gaming" would have to be Lucasarts. A company known for its quality products in a particular genre, specifically adventure games, that were popular but never quite broke into the mainstream in a big way. However, they certainly have their group of diehard fans!