The alternate subject of this post is "DON'T TRY THIS AT HOME!"
I was reluctant to write this post because I'll be called stupid, with a reason.
I set up my Rpi with a powered USB-hub, an external hard drive and connected it to a router as well. I took it to work for bragging purposes and when I came back home late in the night I put the rig together again, turned everything on and went to bed.
The next day nothing was working, so I went to check and realized I had switched the AC adapter for the router and the USB hub, the plug was exactly the same and even the names were somewhat similar (D-Link and Dynex). The AC for the USB hub is 5V and the router's, 12V.
Long story short, the hard drive, the USB hub and the SD card were all fried. But for my surprise, the Rpi board wasn't damaged. Maybe it was, but it's working flawlessly so far. That's amazing! (at least for me).
Bottom line, pay attention when plugging all those cables!