When I hike I carry my Contrail TT and I also bring a 7x9 sil tarp. I know it adds 16 oz to my weight but I don't care. I want shelter from the storms on the trail or a dry place to cook and hang out that is not in my tent. So I guess some would say it is a luxury item. What do others take that might be considered a luxury item but for you it's necessary?