Cyberduck - A libre FTP, SFTP, WebDAV, S3, Backblaze B2, Azure & OpenStack Swift browser.
ExaVault - ExaVault is your Secure Cloud FTP platform -- trusted by over 5,000 companies from Adobe to Zillow. Instant setup for manual and automated transfers with a full web interface and direct FTP, FTPS and SFTP support.
ProjectSend - ProjectSend is a self-hosted application that lets users upload files and assign them to specific clients.
Couchdrop - Couchdrop moves files to the cloud. The Cloud SFTP, FTP, SCP and Rsync server that works with Storage like Dropbox. Up and running in seconds. Fully hosted service. No worries.
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.
SmartFile - Secure file sharing & FTP hosting for the enterprise.