Alyssa Bustamante Gets Life In Prison: 8 More Teen 'Thrill Killers' [PHOTOS]

Alyssa Bustamante, the Missouri teenager who strangled and stabbed 9-year-old Elizabeth Olten when she was 15 herself, has been sentenced to life in prison with the possibility of parole.

Bustamante, now 18, was described as a "thrill killer" who lacked remorse by prosecutors. Though she has since expressed remorse for the murder, she has also said that she killed her young neighbor because she always wanted to know what it felt like to kill someone.

Bustamante, who has a history of severe depression and self-mutilation, wrote in her diary that killing Elizabeth felt "ahmazing." Extracts from her journal about the murder and its aftermath shocked jurors.

But Alyssa Bustamante isn't the only teen "thrill killer" to have shocked and appalled investigators and viewers.

From Eric Harris' desire to achieve "natural selection" in the 1999 Columbine High School massacre to the 1960's road-trip killings by Charles Starkweather, murderous pairs or solitary teen killers have terrified the public for generations.

All of these cases involve child killings or the murder of peers. And in every case, the "thrill killers" either offered no motive for their actions, or felt that the chance to commit the crime was motive enough.

Here, click through our slideshow to learn about eight more teen "thrill killers," from the cold-blooded actions of 13-year-old Eric Smith to the "perfect crime" orchestrated by Leopold and Loeb.

Alyssa Bustamante pleaded guilty to one count of second-degree murder after strangling, stabbing and slitting the throat of her 9-year-old neighbor Elizabeth Olten. The Missouri 18-year-old, who was 15 at the time of the murder, was sentenced to life in prison with possibility of parole on Wednesday.

Dr. Edwin Johnstone, a consulting psychiatrist who testified on Bustamante's behalf in court, said that changes in her Prozac prescription could have played a part in mood swings that may have contributed to Bustamante's murderous tendencies. People who were prescribed Prozac "were showing an abundance of suicides and violent events, including homicides,” Johnstone told the court.

Eric Smith murdered a four-year-old boy named Derrick Robie in 1980. He dropped large rocks on the boy's head, strangled him, and then sodomized him with a small stick. Smith has never explained why he murdered the four-year-old. He has been denied parole five times. "I don't doubt for a second, never have doubted, that had he not been caught, Eric Smith would have killed again," the prosecutor in the case has said. "My fear of Eric Smith is not diminished."

Leopold and Loeb believed that they were Nietzschean supermen who could commit a "perfect crime," in this case kidnapping and murder, without getting caught. For the "thrill" of it, the two exceptionally intelligent teens killed 14-year-old Bobby Franks in 1924 and were sentenced as "juvenile lifers," serving abridged sentences. Loeb was killed in prison at age 30, while Leopold died in Puerto Rico at age 67.

Loukaitis took over Frontier Middle School on Feb 2, 1996 in a hostage-taking incident and shooting spree that claimed the lives of two students and one teacher. A history of mental illness and family dysfunction led to the attack, where the 14-year-old reportedly said, "This sure beats algebra, doesn't it?" a Stephen King reference. Loukaitis is currently serving two life sentences, with an additional 205 years in prison.

Venables and Thompson were not yet teens when they decided to kidnap and brutally murder a little boy named James Bulger, but the reason why they beat the two-year-old to death in 1982 by beating with bricks and an iron bar after sexually assaulting him on some railroad tracks continues to baffle British investigators. Both boys were released in 2001, but Venables was sent back to prison in 2010 for an undisclosed violation of his release.

Starkweather was a spree killer, with Fugate his underage but allegedly willing accomplice. The 19-year-old murdered eleven people in random killings throughout Nebraska and Wyoming during a two-month roadtrip before being captures in January, 1958. He was sentenced to death, while Fugate served 17 years in prison. "Everything was just one big joke to him," Starkweather's childhood friend Bob von Busch recalled. "But he had this other side."

Pomeroy was well on his way to becoming a "thrill killer" by the time he was 11 years old in 1871, when he was discovered to have been trapping small children in a hideaway where he would strip, tie down and torture them. Three years later, after his release from reform school, he kidnapped and killed 10-year-old Katie Curran, and implicated in the death of a four-year-old boy. Pomeroy served life in prison.

Harris and Klebold killed 12 students and one teacher in the 1999 Columbine High School massacre, the worst school shooting up to that point. Although Klebold's motives for the attack were rooted in self-hatred and depression, Harris (pictured) is believed to have been a psychopath with strong sadistic tendencies, obsessed with the idea of "natural selection" and proving his superiority over the "zombies" he was forced to deal with. Harris and Klebold committed suicide the day of the massacre.

Russell and Pearson, both 16, broke into the home of a 90-year-old woman named Marie Oliver in North Sacramento, Calif. in 2006 and beat her to death using her own cane. Footage from their police interrogation show them eating pizza and calmly describing the murder. "Man, we're doin' at least a year [in prison], knock on wood we don't," Russell told Pearson at one point. Both men are currently serving life sentences. CBS has gained rights to the video footage (http://tinyurl.com/77hbcuo).