I have 2 dedicated servers, 1 is a micro atom box which runs mysql, squid, dans guardian, torrents, dhcp, mail etc. And another which is a freenas box holding all my storage. I share the data off the freenas box both via samba and nfs. Samba for the windows and handheld devices and nfs for the shuttle atom xbmcbuntu boxes I have behind the tvs. I have 3 of those and so that I can share what has been watched and the like they all push data to the mysql server.
The freenas box runs a script which pings each one of the front ends on a 5 minute cycle. If they are all offline then it waits 3 mins, pings again and then shuts itself down if it doesn't get a response. All the front ends when turned on send a WOL packet to the freenas box. Total time to boot is 3.5 minutes from pressing the power button on the front ends.
About 5 years ago I paid the money and had a professional run cat 5 through the walls so I have 20 ports all coming back to a rack.
I have also now stuck my main gaming PC in the rack and I use the steam streaming to my laptop when I want to play games (Dell Latitude with full docking station)