Well, I suffer the eternal and very usual "Curse of the GM". As a good friend once told to me: "You will referee the games you would like to play".

And here I am, "working" as a GM with three different groups. Always "in person", I don't know the experience of an online RPG game.
Usually I organize sessions of Traveller: TNE, Twilight:2000 (v2.2), GURPS (3ED) and, more sparsely, Star Wars (D6 system). GURPS only for ancient or medieval adventures or campaigns.
Although I have a few Twilight modules and I'm wishing to use it in an RPG session, I'm in the habit of write my own adventures and campaigns. A good source of headaches for me. And a good source of satisfaction, too.