Free schwag is good. Order online and pickup at a Colorado visitor center.

http://www.letstalkcolorado.com/tshirt/

Sizes and pickup locations have become limited, looks like only XLs and Ms left. I haven't gotten mine yet but plan on picking it up in the next couple of weeks.
I went for the 14er shirt since I'm kinda tired of all the biking shirts I have. Kinda like when I worked at a brewpub and had a million beer t-shirts.