Generally, I avoid posting such things in forum. I personally report cases to admin if there are cheating cases. But I feel that these guys certainly deserve a name in hall of shame.
This happened in March'14:
Pushkar and Vinay Guthal were caught cheating. Both were ranked 2nd and 3rd. Both accounts were banned I suppose.
Reference: http://discuss.codechef.com/questions/39753/interesting-observation
But in April'14, both of them made new accounts here: http://www.codechef.com/users/win_ay and http://www.codechef.com/users/stud_ious and both were again top 10 in April.
Also, this time they cheated, but quite cunningly.