My favorite fabrics are washable silk and washable wool. They aren't easy to find or cheap so most of my travel clothes are some variety of polyester - rayon, modal, tencil, bamboo, coconut husk, nylon (technically they may not all be in the same category).
In my experience all polyesters aren't created equal. Some are very comfortable, breathable and wrinkle resistant while others aren't. I like many of the coolmax type products but not all of them. My advice is try everything on so it at least feels good in the store, then wear it for some physical activity (walk, bike ride, etc.) before packing it for travel.
Also check the laundering directions. I only buy travel clothes that are machine washable and dryable. Even though I often hand wash on the road, I ocassionally stop at a laudromat and wash everything; I don't want to worry about items that need special attention.
It also pays to do a hand wash and hang dry at home to see how the fabric performs before you pack it.
Here's an example of what I pack in my carry-on:
http://www.polyvore.com/cgi/set?id=1440268