I'm a big proponent of wearing sunscreen every day, though I don't think you need to slather on SPF 1000 every day. (Learn more about how sunscreen work, how to pick the best sunscreen for you and how I chose sunscreen for myself.)
Aveeno Hydrosport Sunscreen was my favorite of the summer in 2011, after trying out about 50 (about 99% of which never made it to the blog). This is a chemical sunscreen, so I don't recommend it for young children or those with super sensitive skin.
The Hydrosport collection is water resistant, provides broad spectrum coverage and is incredibly lightweight. I prefer the lotion formulation, which comes as SPF 85 only. It is a thick, white creamy consistency and has a faint sunscreen scent. It absorbs into my skin quickly and I can not feel it on my skin, obviously unusual for such a high SPF coverage product.