Actually for my new watch (http://www.seikousa.com/Product.aspx?productId=145
), not for a knife, but I figured titanium's titanium... I think I remember people talking about touching up brushed titanium with scotchbright or some such.
I figured I'd ask before I took a scrubby pad to my brand new watch!

I figured I'd ask before I took a scrubby pad to my brand new watch!