If you are an American, and an adolescent during the 80s, you probably remember him for his single, "Cars". I can remember the early days of MTV and watching the video for Cars. Gary Numan just stood still without emotion. It was cheesy video but subtlety was not a charcteristic of the 80s.
If you are synth fan, like myself, going back to some of the early music of these electronic bands is still an interesting listening experience. If you listen to yahoo 80s radio stations, you can occasionally hear some of his music in rotation.
In the spring of 2006 Gary Numan released his latest album Jagged. Not surprising it sounds a lot like something Nine Inch Nails might put out.
Listen to Gary Numan discussing "Jagged"(MP3)
Gary Numan Wikipedia