For an in-camp shirt, I second a merino wool product. These things will not smell even after a week in the woods. I prefer IceBreaker, but Ibex is another good choice.

This is one of those things that is pricey but worth it. Watch on eBay and you can get some smokin' deals.

I take a merino wool t-shirt, a long-sleeve zip-neck, and a pair of their boxer briefs. Just rinse out when you can. Doesn't smell at all. Incredible warmth to weight ratio also if you need a layer, but stays cool when needed, too. Great stuff.

When out paddling, I love the Canyon Shirt by Mountain Hard Wear. Collar keeps the sun off of your neck, vented in back to cool down.