The first time I heard of Alexander Brandon was when I was playing Deus Ex and thinking, "who composed this awesome soundtrack using MODs?" (which IMHO is a far superior format to MIDI). Digging a little deeper, I discovered that he was quite an accomplished composer, creating the soundtracks for games like Tyrian, Jazz Jackrabbit, Unreal and Thief.
Fortunately, he's still in the business of creating music for games, but I'm not quite sure how much actual composing he does nowadays as he's had several roles as an "Audio Director", his most recent post being Audio Director at one of my favourite development houses, Obsidian Entertainment. The last game he has been credited on was Neverwinter Nights 2: Mask of the Betrayer. He's apparently now working on the soundtrack for the next expansion, Neverwinter Nights 2: Storm of Zehir.
To celebrate his awesome music, I just got a random sample of fan-made videos that play his music. Enjoy!