Just real quick: Don't "go viral". EVER. And show every marketing guy saying something like "uhh.. nice and then we can make it go viral" the door. He is bad for your business. PERIOD.
You wanna know why? Ok. I'll tell you why.
Viral Marketing in a nutshell is the idea of mouth-to-mouth, the most basic way of marketing ever. People talk about it, friends share it with friends and soon you get the "what? You don't know X"-Effect. A Dream for every marketeer. The idea behind viral marketing is to analyse how this effect comes up and what needs to be done to make it happen. And all that as fast as possible. Specially with these new tools existing in social media this kind of marketing comes off very cheap and there are quiet some companies offering the service as a part of Guerilla Marketing today.
What these companies don't tell you is that they actually don't have a clue. All they offer you is a basic set of tools which make virus-like spreading possible but they have no idea which idea actually works and why. Some do and others don't. Most of the time it only works at this crucial moment with this sound in the video and this bad colors and and and... Before it started no one knows if it will "go viral". And that is true for your idea as well: you never know if it can successfully go viral. Not until it did, but probably it won't.
Most of the time you can't "plan" viral. Not in the big picture. Like the trololo-guy. 30 Years after he sang the song it appeared on YouTube and got more than 1.5 million views (by the time of this writing). Now he is singing the song again, in clubs all over Moscow and the people love him. But that wasn't part of the plan. Especially, it wasn't HIS plan. The user who uploaded the video has no benefit from this success in one way or another. And that is why it worked. If you have the goal to make it "go viral", you probably won't succeed.
Well, but that is wrong as well: "going viral" is so easy that there is almost no reason in doing it at all. Because you can't measure it. When was a Video successful? After it got 100k views? after 1mio? After it was shared 2Mio times? Or 200k? Or even 20? You can't actually measure it, so marketing people can always pretend that their ideas were good and were working.
And you probably don't even want to have something go viral. Beside the obvious possibility of it turning against you and what you wanted, there is an even bigger thread. Going viral can even harm your business. Lets think a of a nice local wine shop. Every two weeks they have an open wine tasting, everyone in the city loves it, especially the wine lovers. For some reason one really funny video of one of these tasting ends up on youtube and "goes viral".
Over the next a couple of month the wine tastings are overcrowded with young people who can't quiet afford the wines there but laugh a lot. At some point the owners decide to expand their business to manage the big crowds. They hire more people to manage the crowds. Less and less of the regulars come by, the tasting just lost its special touch and the new place feels to big and not familial any longer.
After the hype is over (and at some point it will be. always!) the owners stand in front of a dead business: they have more salaries and a higher rent to pay but fewer of their regulars come buy and the expanding costed more than the new audience brought in over the last months. Now they realise that going for the new audience was wrong. They should have gone for smaller growth on the regulars they already have. But now it is too late.
And like this one most small and mid-size businesses aren't capable of the "big rush over night". So when it happens they have to change too much too quickly. Afterwards they can call themselves lucky if they lost only their identify, most of the time they also loose their regulars, employees and their main goal. Instead of going viral and aiming to become "the next big thing" for most small and mid-size businesses it is more healthy to go for a slow, constant growth and keeping their current customers happy.
Long story short: Be happy that you aren't viral. In the rush of a hype you are tempted to do something very stupid. And only few people are able to resist it. So, next time someone offers you to take the marketing "viral", point him to the door, pick up the phone and call one of your regulars; invite him/her over for a nice dinner. It is even cheaper than going viral and doesn't harm your business!
Updated 3rd May 15:00: I was told that the article missed the point. Therefore I added another paragraph before the last one, explaining in-depth what I mean. I think the message is much clearer now.