Sign up at Yunpan.360.cn to get 360GB of free storage. (can be extended up to 36TB by downloading the PC and Android/iOS clients)
Sign up at Ozibox.com to get 100GB of free storage.
Sign up at SurDoc.com to get 100GB of free storage.
Sign up at Shared.com to get 100GB of free storage.
Sign up at Adrive.com to get 50GB of free storage
Sign up at Mega.co.nz to get 50GB of free storage.
Sign up at Hubic.com to get 25GB of free storage.
Sign up at Firedrive.com to get 20GB of free storage.
Sign up at Onedrive.live.com to get 15GB of free storage.
Sign up at Copy.com to get 15GB of free storage.
Sign up at Mediafire.com to get 10GB of free storage. (40GB more available with other activities)
Sign up at Pcloud.com to get 10GB of free storage (10GB more available with other activities)
Sign up at Box.com to get 10GB of free storage.