With the news that the ailing 'Smallville' has been renewed for a tenth season we take a look at shows that killed themselves by going on too long.

Once you've read our list, you can leave a comment to tell us what you think!

(Note: This list doesn't include reality television shows or soap operas. Otherwise it would be a lot longer.)

Smallville

The original idea for this show was fantastic. Clark Kent growing up, coming to terms with his powers and his massive crush on Lana Lang - and saving Smallville from meteor-infected super freaks. Throw in a very, very pretty cast and you have television genius. And the show was a massive hit for a long time. And now, storylines are getting stale, two of the show's biggest stars have disappeared and it's all just got a bit much.

Desperate Housewives

'Desperate Housewives' was great fun when it first came out. A funny, sexy and clever cast managed to find the line between soap opera and prime-time drama in a show that kept viewers glued to their sets. It was all going well? and in an act of ratings suicide, the show then jumped five years into the future. Um, sorry what? Any relationships you may have had with the supporting cast were shattered. That move was a little too? um? desperate.

Heroes

Another show with a mind-blowingly awesome first season. The plot was well-written, the actors were all really pretty, and the show's "Save the Cheerleader, Save the World" has become a pop-culture classic. The idea was great - sexy people trying to come to terms with the sudden emergence of "superpowers", all realising that they are interlinked. And then season two happened. It started with Hiro stuck in feudal Japan (um, okay) and Peter's memory being wiped. And now it's just way, way past its sell-by-date. The crew have their heart set on season five, but it is yet to be confirmed.

Scrubs

Now I've never been a huge 'Scrubs' fan, but I know people who were on the verge of obsessed with the show. And even they agree that the last few seasons were pretty lame. Before there was 'Grey's Anatomy', these guys were the sexiest, funniest interns on television. But after the first few seasons, it started losing its way a little, and has been on the verge of cancellation a number of times. After their star Zach Braff called it a day, they should have pulled the plug. Instead, they soldiered on through a ninth season, bringing in almost an entirely new cast.

Lost

At least the crew of this show have set themselves an end date. 'Lost' was another one of those super-fashionable shows that started out with a massive bang (or in this case, a plane crash) and just got too big for its boots. I know that a whole lot of people don't agree with me on this one, but I really think 'Lost' should have cut its losses and just been one of those "Omg, wow!" shows that stopped after two or three seasons. The main plotline got way out of hand, viewers were left with a big "huh?!" and the characters' interactions - by far one of the best things about the show - became tired and stale.

The Simpsons

"What?!" I hear you cry. "The Simpsons are an institution!" Yes, but they've also been running for twenty years. Shows that have been running for that long are bound to get a little stale. Another case of a show that should have been cancelled while it was still in its prime.

On page two: They noticed too late...