Wacom Cintiq 12WX. Brought from a good friend of mine.
For years I had drawn everything by hand with pencil and then reworked over it all again with pen/ink. It was very time consuming and when I made a mistake with the ink, my heart was broken after all the hard work I had put in. But with the Cintiq, any mistakes are quickly recovered. The speed I can work now, when compared to paper is so much faster. But it does have some flaws, Which I can over look in time.
But it's still some serious kit.