If you're looking for a different look than the increasingly mass market Banana Republic/Gap look, give Kweejibo a shot. The shirts are a basic cut (regular and a slimmer "fitted") and come in long and short sleeve. If you don't like how the shirt fits, you're out of luck. The hard part is picking a pattern from the wide variety of materials and styles. The shirts are a little pricey, but it's worth it so you don't have to worry about showing up to work with the exact same shirt as your co-worker (especially after a big Banana Republic sale).
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