I have worn the same clothes for the last 8 weeks. Backpacking clothes are often durable, smell-resistant (natural fibers, not synthetic), and stylish.
I wear an icebreaker longsleeve quarter-zip baselayer ($40 on sale), icebreaker quarter-zip midlayer ($60 on sale), exofficio fleece ($50 on sale), REI adventure shorts ($30) or REI adventure pants ($50), smartwool socks (a gift from the in-laws!, but ~$15), and exofficio underpants ($10). I wash the undies and socks regularly (can be done in a sink), and the baselayer approx. every 2-4 weeks. I have had each of these items for 1-4 years and they still look damn good.
Einstein, Henry Rollins, Steve Jobs, etc. realize that fashion requires thought/care. Don't care!