Curtis Armstrong has been nerd royalty for 30 years, but he wasn't always comfortable with the role that made it possible.

The actor embraces his geeky stature these days as executive producer and co-host of TBS's "King of the Nerds" reality competition series, which is scheduled to start airing its third season in January. He also recently reprised his role on CW's "Supernatural" as Metatron, the bookish scribe of God who enacted perhaps the ultimate case of nerd revenge before he was defeated and imprisoned...