Using Skype in TV mode on a Mac Mini I've got my mac mini hooked up as a media centre - using Plex - and it's great!

I control everything with a Logitech Harmony One.

One thing I've wanted to get going is Skype on the TV.  I have a webcam I can hook up to the Mac Mini, however the Mac version of skype does not seem to contain a 'couch mode' that can be controlled via a remote.

Is there any way to install Skype on my Mac Mini, and make it easy to use with a remote?
I have much the same setup as you and therefore ran into much the same dilemma, so the following may not answer your question, but it might help! 

I began by using Remote Buddy's "Virtual Mouse" function to use my Apple Remote to navigate around Skype using the directional buttons to move the mouse around (once contacts are set up, its mostly moving and clicking). However, I'm the first to admit this is a bit clunky and not exactly ideal. (I realise you're using a Harmony One, as opposed to an Apple Remote, which doesn't appear to be officially supported, but it looks as though its possible to pair it with Remote Buddy).

In the end, I gave in a bought a Logitech diNovo Mini which is good enough for when I need a keyboard and mouse. And you can also use it for some Couch-friendly surfing too :)