Is there any way to attach a third external monitor to my 13" Macbook Retina?

I was really disappointed to learn on Friday that my 13" retina isn't capible of powering three external screens. I had two DP to VGA adapters plugged in, and the HDMI. Immediately two screens lit up. However, one remained black. I thought closing the laptop lid would free enough resources to allow the third screen to display, but no go 😟

I would so very very much like three external screens that I've been investigating my options:

1) Return it and get the 15". I actually tried to do this, but I stupidly threw out my box even though I only got the Macbook ~8 days ago. Apple wants all packaging and manuals, so this isn't quite possible. My next option is to sell it on Craigslist or something at a loss. Not exactly ideal.

2) Split the signal of one of the connections by using something like Matrox's DualHead2Go. Not ideal though because it's likely one screen spanned across two monitors.

3) Get a USB to VGA adapter. I'm not even sure if this would work, but it seems like my best bet.

Also if it helps my monitors look like this:

Left: Small VGA 5x4 screen.

Center: Large DVI 16x9 screen.

Right: Another small VGA 5x4 screen.

Does anyone have any suggestions for this poor ******* who didn't do enough research before buying his Macbook Retina?

Thanks!

John

Also, I would rather not use the retina screen when using the external monitors. I prefer either just the retina or just externals. It just feels weird mixing externals + the laptop screen.