Drugs on TV have had a strange history. There have been after-school movies, very special sitcom episodes and even entire dramas based around illegal substances.

Sometimes, drug abuse on TV is used to teach the audience a lesson, while other times writers have characters develop an addiction as a way of making them more human in a flawed sense.

One of the most recent drug abusers comes to us in the form of Edie Falco's title character on 'Nurse Jackie.' The medical drama is back with a vengeance (Mon., March 22 10PM on Showtime), and to celebrate the return of our favorite no-nonsense RN, we're taking a look at TV's other famous pill-popping characters we've come to love (despite their issues) over the years.

We're not endorsing drug abuse of any kind, but it's a fact of life for some people, including these TV characters.

Find out who made our list after the jump.

My sister was addicted to Saved by the Bell, and to the hotness that was Zack Morris in particular. I'm not sure if she checked out Late Night With Jimmy Fallon last night, but if she had she just might have been stunned to see Zack Morris there. And I do mean Zack Morris, because Mark-Paul Gosselaar did his entire interview in character as the coolest guy from Bayside High.

Considering that Gosselaar has been doing pretty well for himself post-Bell, with big roles in NYPD Blue and Raising the Bar, it's a big deal that he was not only willing to poke fun at his own roots (with The Roots as well for a rousing rendition of "Friends Forever"), but he also committed to Fallon's pet project: the Saved by the Bell reunion. Personally, I think a funny take on where those kids are today could be awesome. You could even work Showgirls into Jessie's post high school career path.

Jesse Spano is coming back to TV. After guest appearances on CSI: Miami and Law & Order: Criminal Intent, Elizabeth Berkley is ditching the procedurals and heading over to Showtime. The former Saved by the Bell star will be joining Jennifer Beals, her costar in the 2002 film Roger Dodger, on Showtime's The L-Word for a multi-episode arc.

Word is, Berkley's L-Word character has a history with Jennifer Beals' Bette. The two went to college together and Berkley was the straight girl who got away. Perhaps Bette will have better luck the second time around.

My only hope for this pairing is that they can somehow manage to fit a Flashdance: What a Feeling / I'm So Excited dance-off into the plot of the show, thus bringing together the high points of both of these women's careers and officially making this the best casting decision ever.

While Elizabeth Berkley's TV pedigree was perhaps better received than her feature film debut, it was the notorious Showgirls that made her a household name and launched her into the "Worst Films Ever" hall of fame. Her career began in the teen series Saved by the Bell, which also netted us Dancing with the Star's Mario Lopez, NYPD Blue's Mark Paul Gosselar and Beverly Hills, 90210's Tiffani-Amber Thiessen.

After Showgirls, it took the actress many years to regain credibility and acclaim, working in theater and off-Broadway productions until her return to television in 2002 in a recurring role on Titus. Since then she has guested on several shows, including CSI: Crime Scene Investigation. Now, Reuters tells us the 35 year-old Berkley is set to play Horatio Cane's (David Caruso) ex-wife Julia Winston and mother to his recently discovered teenage son (Evan Ellingson) on spin-off CSI: Miami. Miami is known as a "hotter, sexier" CSI, so she should fit right in. She can even try to match Caruso's one-of-a-kind line delivery when they inevitably spar.

Dustin Diamond is really starting to get on my nerves. First, in order to change his image from the screechy-voiced character he played on the NBC Saturday-morning sitcom Saved by the Bell he became a foul-mouthed comedian (like we don't have those already). Recently, much to the anger of his fans, he decided to sell $20 t-shirts to save his Wisconsin home from being foreclosed upon.. And now, he's giving out sex advice saying, among many things, that he could write a book on the sexual moves that he has tried and tested and that you need to tap your partner so hard they fall asleep.

I don't know if this is some sort of long-term plan of Dustin's to have us forget that he played the role of Screech for nearly a decade. Or, maybe it's just him trying to drum up some new publicity for himself. I can't read his mind, so I don't know the definitive answer. However, I do know one thing . . .

No matter what he does, he'll still be Screech.