Seems to be working quite nicely. You set the options in gconf (it's a gnome app) for which tag you want to use and what interval for the slideshow you want, and then just run the program. It will use any changed config options each time it changes, so if you set it to one tag and then run it and change it, it will use the new tag the next time it changes.

The next stage is to write a config front end so you don't have to edit gconf, and then write an install program (at the moment you have to manually insert it as a new program to start up as part of a Gnome session). Problem is, it works fine for me, so the motivation to do that is not so high. Hopefully I'll get around to it soon.

And I have to say, I've quite enjoyed the experience. E17 is a very well put together desktop environment. Things I love:

1. The amount of control you get over your windows (it can optionally remember which virtual desktop, size, postition, etc. you want an application in, as well as conveniently being able to start it at login and/or pin it to the desktop). Very nice, as Borat would say.
2. Low resource usage for nice bling - and not so much bling as polish really. Try it and you'll see what I mean. It's a good looking desktop, no doubt.
   
3. I like middle click on the desktop and you get a list of open windows. Switching to other windows is remarkably easy after a while.

Things I prefer about Gnome:

1. Transparency with compiz/beryl
2. Expose like feature of compiz/beryl
3. Integration of Gnome apps such as rhythmbox, etc. E17 still doesn't have a systray - I use trayer to get around it, but it's not ideal. It's a blight on an otherwise great desktop for E17.
4. Avant Window Navigator. Cover album integration is too nice.
   

I have to say, at this stage I'm not sure whether I'm going to stick with E17 or Gnome. Stay tuned....

In the end, the setup wasn't too bad, but it did take quite a bit of getting used to. Not the most intuitive process.

Basically, get yourself set up with Ekiga, which on Ubuntu Edgy is available in the Ubuntu repos, and then once you've signed up for an Ekiga account (which you can use for PC-to-PC calls) you can also sign up for a PC-to-Phone account. I chose to use the one that's built into Ekiga (with Diamondcard ), as I figured it would work better, but also that there might be some kick back to the Ekiga project from Diamondcard, so that supporting it would be a good thing. Not sure if I'll stick with them once I'm all set up - will depend mostly on call quality and rates.

In any case, the big gotcha for me was that I was getting "Security check failed" even after I'd verified that I had everything set up correctly (which I could do by going through the configuration wizard, and then calling the "echo test" (which just repeats back to you whatever you say to it to show it's hearing and to verify you can hear that) at "sip:500@ekiga.net". I put in a support request to Diamondcard, and got a return reasonably promptly telling me that I didn't need to include the first "00" for my call. So, for instance, to call a number in the UK such as 0207 123 4567 you would call "sip:442071234567" not "sip:00442071234567", as I'd seen in some of the online docs.

Anyway, all set up and looking forward to using it, being able to track call history, and seeing what other benefits IP telephony can bring!