I think Jonghyun from CNBLUE and Jaejoong from DBSK are really alike... and i mean REALLY alike. 

Reasoning:

1)Both have sort of an airy(?) voice when they sing

2) drama actors

3) similar jawline

4) INTENSE eyes

5) Although both give a rock music feel, their voices also work well with ballads

6) During their debut, both had hair that reached their neck and longer

7) ABS ABS ABS ABS ABS ABS ABS ABS ABS ABS ABS *cough*abs*cough

lol but yeah, i think they are alike ^^"