If you have thought, "Where have I seen him before?" like me, I found out where I have seen him before.

I just bought a larger screen TV and decided to watch a movie on VHS to see how it looks. I had a smaller TV (much smaller in comparsion), so I put in Saving Private Ryan. Nathan Fillion played the first Pvt Ryan that was told that his brothers were killed in combat to which he replied they were still in grammar school. Wrong Pvt Ryan.

What else has he done?

He was in Dracula 2000 and "Two Guys, a Girl, and a Pizza Place". (I think he played the "Girl"s boyfriend.)

Thanks, Charles, for the info.

I'm surprised no-one picked this up - Joss Wheedon obviously liked Nathan enough to take him onto Buffy - he was Caleb.

Out of the remainder of the regular cast
Gina Torres was Jasmine in Angel (S4)
Adam Baldwin's just done Season 5 of Angel
And Summer Glau was the ballerina in the Angel episode "Waiting In The Wings" (S3?)

""Two Guys, a Girl, and a Pizza Place". (I think he played the "Girl"s boyfriend.) "

Yes, then fiance, then husband. Also the show later dropped the Pizza Place and was just "Two Guys and a Girl" even though by that point it was more like three guys and two girls or something like that. Oh, his character was named Johnny. I think. Been a while.

I'm kinda curious to see this because he's in it.

This clip from a recent episode Castle was cute. NOTE: To get the full effect of the humor, try not to read the text surrounding the video player, which gives the gag away.

I thought Nathan Fillion was a little too young to play this part convincingly. Mal's portrayed as this grizzled veteran from the wars, calls the doctor "son," but looks like he's about 30.

He could, of course, be 30 and have experienced the Alliance war, but his dialog sounds like it should come from someone older. Doesn't help when he tells Kaylee he's a "mean old man."

Appearances aside, Fillion does an outstanding job of actually being a mean old man; he just doesn't look it.