Hint: if you don't know what Raspberry Pi is (for real? o_O), check this video: http://www.raspberrypi.org/help/what-is-a-raspberry-pi/
Now, when we've covered the basics, let's summarize ...
... the recent announcements
Few days ago Eben Upton has announced that a new version (2 Model B) of Raspberry Pi is happening & ... it's on sale already: http://www.raspberrypi.org/raspberry-pi-2-on-sale/. Pricetag doesn't