The New York Times recently ran an article about how to extend the life of your vacation. Along with novel ideas like taking photographs and buying souvenirs, it suggested you wear clothes you bought while travelling. I DO NOT RECOMMEND THIS.
If you come back from your Machu Pichu trip wearing one of those Peruvian ponchos to work, you will look - and actually be - ridiculous. Unless, of course, you are also carrying a pan flute. In which case, you will be a source of awe and wonder.