DelaFil - Share files in an easy way. One, two, three and its Sent! Instructions:
Uppy - The next open source file uploader for web browsers
WeTransfer - WeTransfer is a free service to send big or small files from A to B.
Filestack - Simple file uploader and robust APIs for uploading, transforming, and delivering any file into your app. Filestack is a collection of tools and powerful APIs that make it simple to upload, transform, and deliver content.
MediaFire - MediaFire is the simple solution for uploading and downloading files on the internet.
CloudExplorer - Cloud Explorer is a open-source Amazon S3 client.