Picked up a parts set for the SDCC Rocket Raccoon Warbird off Amazon. Nice little build - not sure if I'm going to pursue getting the "official" SDCC set or not. The parts set is all Lego pieces, so the only thing I don't have for the set is the official instruction book from Lego and the box. Not sure if those two things are worth $100+
To extend my Marvel Collection, I also started looking into the knock-off stuff out of China. While they do make sets and minifigures that are exact copies of stuff Lego makes, they also make stuff that Lego doesn't make (or at least hasn't made yet).
So far, I've gotten a set of 9 Iron Man minifigures and four "big" minifigures from a company called "Decool" - the big minifigures are great - Rhino, Venom, Juggernaut and Hulk Buster Iron Man. In the Iron Man 9 figure set, there were some pretty cool armor variations, including a really neat Mark I set of the armor.
Here's what the Hulkbuster Looks like:

and here's the Venom big minifig:

and here's a pic of the set of 9 Iron Man figures:

And then from another company called Shang Yuan (their stuff has an "SY" logo on it), I picked up this set of 8 Captain America minifigures:

Lastly, also from SY, I picked up these two Iron Man sets:


Prices are pretty cheap and if you're willing to wait 2 weeks for the stuff to come from China, you can find an eBay seller who will ship for free, which is pretty crazy when you think about it...
The "SY" company also has a pretty cool wave of 8 Spiderman figures that I'm thinking about getting, and their Groot mini-figure is pretty cool too since it's mini-figure sized (not outrageously large like the Lego version). On the Decool side they have a nice set of Fantasic Four minifigures AND Future Foundation variants that I'm keen to pick up, plus their Thing big minifig is pretty spot-on for matching the version of Thing shown in the Lego Marvel Super Heroes video game.
So while I don't necessarily "condone" supporting bootlegs, if Lego were to come out with any of these minifigures or sets, I would gladly throw aside these in favor of having the real-deal.