Having studied linguistics and a foreign language in college, language-based humor never ceases to amuse me. The Berlitz Corporation uses comedy in most of its television advertising to reach a wide audience. My particular favorite is a 2006 Norwegian commercial that seems to claim that language barriers can be very detrimental--possibly deadly--in certain situations.
Since its release, the commercial has garnered millions of views and fans all over the world. The video begins with two men in a control room of the German coast guard. There's a new employee being shown around briefly, and then he's left to fend for himself. It becomes clear that his English skills may not be quite up to par with what the position requires when a voice comes over the radio asking for help. The voice tells the man that they are sinking, which to a German ear can sound like "thinking," and lo and behold the German man responds by asking the sinking ship what they are "sinking" about.
This video, like all ads like go viral for their creative humor, is effective because of the massive audience it won. Defining a target market for language courses is difficult; everybody has their own unique reason for wanting to learn a foreign language. There may be some broad categories of potential language learners Berlitz uses to plan its marketing strategy, such as people who want to improve their English skills for business reasons.
The advantages of the services the Berlitz corporation offers are slightly more abstract than many products and services we see advertised on a daily basis, so it's important that Berlitz stay creative and use situational humor to reach its target audience. In America there is especially little enthusiasm about foreign language learning, largely due to a lack of understanding about the ways foreign language skills can be beneficial to a particular individual. Berlitz uses humor to help get these benefits across in an effective manner.
There are other videos, like this one and this one, that highlight other reasons or benefits for improving skills in a foreign language. Berlitz also released an "ad" this year for their new Klingon services--to which they added an April Fool's Day disclaimer that was naturally missed by many people. Overall, I think Berlitz's marketing campaign is a successful one for the kind of industry and helps their name stick out among competitors'.