Just a quick post of how to update a low memory system by ssh.
OwnCloud is a great dropbox/ubuntuOne/GoogleDrive alternative. Gives you the power to run your own server without having to worry about others controlling your data. I also think the features of owncloud are better than most of the other services. This article will explain how to install ownCloud on a Ubuntu 12.04 LTS server.
Screen is a linux command line tool that allows you to store sessions and create windows without a GUI. This article is just a quick little "cheat sheet" for me to remember the screen key bindings, but you're welcome to read.
There seems to be an issue with the update from Joomla 2.5.4 to 2.5.5 or 2.5.6 that causes sendmail to stop functioning in less than PHP v5.3.10. This article explains how to recover from the "Could not instantiate mail function." error after an update.