6. Gareth Bale
Although unlikely, the idea of a rich club paying more than £86m in order to sign Gareth Bale within the next three or four years shouldn't be ruled out entirely.
Of course, only a few clubs in the world would be able to finance such an astronomical deal, but there will inevitably be interest in the Welshman, who has not looked out of place at the Bernabeu since leaving Tottenham last summer.
Bale is currently very happy in Madrid, but what if his situation changes in the near future?