Humour can be a powerful tool in websites design. It can help to reduce stress, promote happiness and build rapport with your audience.
There needs to be a connection between what you are selling and your audience, so using that connection is key to deciding if humour has any place at all in the content of your website.
One of the best ways to determine if humour is appropriate in your website design is to pay attention to what kind of person you are designing for.
If you are designing a website for a professional who is looking for a serious subject, humour might not be appropriate. If you are designing a website for a younger audience, then it might be appropriate to use humour in your design.
Any subject matter can have comical aspects that can be used to further engage with your audience, but only if the topic allows it.
Humor in website design is only appropriate when you are designing for a professional or business owner who is seeking to amuse his audience with tales of a life lived or jokes that resonate with the consumers.
The about us page can be used for just this purpose but be careful!
I use this technique myself on my contact page, (it doubles as an about page) and some people will see it and love it but other will probably say - "what an asshole!"
I really don't worry about that because I would not want to work with anyone that thought "what an asshole" anyway.