If you're looking for a tent that you can take with you anywhere, check out the World's Toughest Ultralight Survival Tent, a two-person mylar shelter that could fit in your pocket.
The tent is made from NASA-designed mylar, which reflects up to 90% of body heat. It's held together by 425-pound test paracord, and weighs a mere 9.5 ounces. If you don't use the tent as a shelter, you can use the mylar as an emergency sleeping bag.