Open Cloud is a generic term. There are many large storage companies that offer cloud services, but, you would be syncing your files out in the cloud, and, for me, that decreases my privacy. Owncloud, which allows you to set up a cloud service on your own machine, is the way I would go. If it's not available in your distros repos yet, here's a how-to from the Debian based distro I use, siduction.

http://news.siduction.org/2012/09/owncloud-as-an-alternate-to-dropbox-and-friends/