xfce

[norman]

This afternoon I switched off my PC to do some cleaning. When I switched
back on I was presented with a screen, the colour and layout of which I
had never seen before. The screen was blue, all the icons were
different, there were no top and bottom panels and the applications etc
were accessed by right clicking the mouse button. The only clue I could
find were the letters xfce. 

I use Ubuntu 7.10 and I have absolutely no idea what has happened. If I
didn't know better I would think I had been attacked by a virus. Do you
know what has caused this to happen?

Norman