No.1 Dark Lord, T. M. Riddle-- I mean, Lord Voldemort.
No.2 Bartemius Crouch
Bartemius Crouch Jr., Voldemort's most loyal servant. Of course he gets to be number two.
No.3 Bellatrix Lestrange
Bellatrix Lestrange, the lone female Death Eater. Fanatical and obsessed, not to mention somewhat insane. Azkaban will do that to a person.
No.4 Peter Pettigrew
This rat Animagus sacrificed his right hand as part of the potion that restored Voldemort to a body, and was given a much stronger silver hand as a replacement.
No.5 Lucius Malfoy
Brother-in-law of Bellatrix Black Lestrange through his wife Narcissa When Voldemort returned in June 1995, Malfoy returned to his old master (GF33).
No.6Rookwood, Augustus
No.7 Igor Karkaroff
When he realized that Voldemort had returned, Karkaroff fled for his life.
No.8 Macnair
No.9 Severus Snape
This one is my favorite
No.10 Rodolphus Lestrange
No.11 Rabastan Lestrange
No.12 Mulciber
No.13 Antonin Dolohov
No.14 Avery
No.15 Greyback
No.16 Regulus black
No.17 Nott
No.18 Crabbe Sr.
No.19 Goyle Sr.
No.20 Alecto Carrow
No.21 Amycus Carrow
No.22 Travers
No.23 Yaxley
No.24 Thorfinn Rowle
A large, blonde Death Eater who broke into Hogwarts the night Albus Dumbledore was killed (HBP28). He showed up again later that summer, following Harry, Ron, and Hermione into a café along with Antonin Dolohov; after failing to capture Harry that day, he was punished severely by Voldemort.