Recently I found a nice article about home automation using open source software and OS Linux. It covers all aspects of smarthome - appliance control, media recording and streaming, security and surveillance system, telephony. Actually this is a brief overview. So, don’t expect to find there detailed instructions how to automate your home. But as a start point is really helpful.
P. S. LinuxMCE basically offers all features described in that article and much more.
The open source software to watch Internet TV Miro was lunched recently. It turns your PC into full-featured media center. The main idea of Miro is offer en easiest way to browse, search, watch and store a video content (even HD) delivered by internet connection. Using Miro it’ll be easy to watch and store video from sites like YouTube or Google Video. It offers a simple interface to download video files from BitTorrent. It can be stored and played after on your PC. Also you’ll be able to watch thousands Internet channels, video blogs or podcats. Additionally, Miro can play Quicktime, WMV, MPEG, AVI, XVID video files stored on your PC.
The first version of Miro is available for Linux, Windows and Mac OS X. So, you have a various choices 
[via eHomeUpgrade]
Recently I discovered Ubuntu Home Server Project. As project creators say:
Ubuntu Home Server (UHS) will be an edition of the Ubuntu operating system which allows users to administer their home network. With Ubuntu Home Server you will be able to store all your music, songs and pictures in one central location, to access your files over the internet and to backup all the computers in your house.
So, hopefully we’ll have a good alternative to Windows Home Server. Especially, Ubuntu has the most attractive user interface IMHO. Also, we should take into account that recently open source home automation system Plutohome was ported to Kubuntu. I can see the good tendency that two great software product for home are concentrated on the same OS.
Recently I wrote about home automation with Python. The good opportunity to do that is using your preferable program environment and automate your home. Today I found another good project - jHomeNet. jHomeNet is Java Home Automation system based on Java, of course. Since it’s Java the system supports any operation system (at least Linux, Windows and Mac OS) where Java can be run. It also needs Mysql database. Currently jHomeNet allows to control 1-Wire and x10 devices only.
The first release of jHomeNet was on August 2005. Since that time the system can do a few things only (according to user’s manual). But as I see jHomeNet includes an application server and there is a chance that it will be expanded to the other area of the house and will support more devices.