S3 and load balancers (with ACM support). Having a magic load balancing appliance that autoscales and supports TLS termination is nice and reduces a lot of maintenance. There's nice value adds like OpenIDC support.

S3 is incredibly powerful and cost effective for the price. It has insane throughout and a very simple API (compared to, say, setting up SMB or NFS to support public uploads where you need more pieces)