Ooooooh Tabletop RPG convo? (so it's a bit old...but lets see who is still around)
I've been GMing for yeeeeeeears...yes forever GM

(but I secretly love it)
I'm currently running a Dark Heresy campaign with 6 other people over Roll20 and Skype. It's been going for over a year now and is just coming to it's bloody conclusion.
I'm also playing in a Call of Cthulhu campaign one of my friends is running (he is trying out GMing for the first time, tis going ok, even if I do oft times take it off the rails just for a bit of payback from all the years of them doing the same to me!)
Once the Dark Heresy ends, (should be in the next week or two) I'll be starting an Elder Scrolls (Focusing on Skyrim) RPG using an unofficial modification of the Warhammer Fantasy RPG rules, (looking forward to this quite allot, as all the players are familer with the franchise and all the groundwork/worldbuilding is already there, so I can let them run off the rails if they need to without having to completely make stuff up on the spot)
Also planning to take part in a New World of Darkness game (Vampire the Requiem) some time in the future, (another friend wanting to try GMing). His only description he has used so far is "Charlie's Angels...but with Vampires"...should be interesting!
And I also have a couple homebrew settings I run one-off games for every now and then using the Savage Worlds ruleset.
One setting is a funky fantasy setting where the players all play as races that would be typically considered "Monsters" "Centaur, Merfolk, Driders, Harpys, Insect men, Sentient Armour, Mutated Humans etc). Groups are hired and sent off to explore and salvage things from the ruins of an ancient civilisation, because hell...what sane human would go trekking through the wilderness and into dangerous uncharted ruins on the hunt for treasure that might not even be there? Especially when the world is full of creatures that would eat you as soon as they saw you! Yes...the smart thing to do is hire some monsters of your own, if you want the job done properly that is!
The other setting is a post apocalyptic superhero setting, where most of the population was wiped out by an evil villain's successful plan, and the survivors are struggling to rebuild. All the usual post-apocalypse tropes are in place, (raiders, scarce supplies, mutants, if you have played any "Fallout" games you get the drill) with the added exception that the players each have a couple minor super powers at their disposal. (Think "Heroes" if you ever watched that show). So players have to walk the line of using their powers to overcome their problems, while also attempting to hide them in public (as the general populace will flee or kill "Supes" on sight since they are not trusted any more). Tis good fun.
Phew...sometimes you don't realise how much time you spend on that stuff until you write it all down!
I would love to get a group together from here one time, even just for a one off game or two, I do most of my GMing over the net now anyway, as all my friends are scattered across the country, so I would happily run something ^^;