Truck - A faster alternative to FTP
fruux - Free service that takes care of your contacts, calendars and more so you don't have to.
MirrorFolder - MirrorFolder is a real-time folder synchronization and backup software
FullContact - Put the power of full contact information into your web or mobile apps.
CopyQueue - CopyQueue - Copying under control.
Google Contacts - Google Contacts is Google's contact management tool that is available in its free email service Gmail, as a standalone service, and as a part of Google's business-oriented suite of web apps Google Apps.