For those who took part here are the answers to the quiz:
1. Chris Hoy
2. Fern Cotton
3. John Barrowman
4. Rachel Rice
5. Lily Allen
6. Chris Martin
7. Heath Ledger
8. Barack Obama
9. Lewis Hamilton
10. Peter Kay
11. Jeremy Clarkson
12. Paul Newman
13. Heather Mills
14. Kelly Osbourne
15. Tom Chambers
16. Katie Price
17. Boris Johnston
18. Davina McCall
19. Usain Bolt
20. (Robyn) Rihanna (Fenty)
21. Carol Vorderman
22. Melissa Joan Hart
23. Russell Brand
24. Robert Peston
25. Harrison Ford
26. Guy Richie
27. George Sampson
28. Fernando Torres
29. Paris Hilton
30. David Walliams
31. Judi Dench
32. Naomi Campbell
33. Miley Cyrus
34. Andy Abraham
35. Ian Smith
36. Seth Rogen
37. Laura Robson
38. Alexandra Burke
39. Alistair Darling
40. Rebecca Adlington
41. Jamie Oliver
42. Fiona Phillips
43. Luiz Felipe Scolari
44. Joe Swash
45. Amy Winehouse
46. Peaches Geldof
47. Jason Donovan
48. Gordon Ramsay
49. John Sergeant
50. Tina Fey
Congratulations to Ross Pepper who managed to get 47/50 correct.