Made-up languages, part 1

How many of you have actually made up a language, even during early childhood? Here are two basic examples of such languages.

Op-talk: Insert the letters "op" after each consonant in the word, and leave the vowels alone. Example: yes -> yop-e-sop

Gibberish: Insert "udda-g" after the first consonant in each syllable of the word. Example: yes -> yudda-ges

Why invent a language?

A reason to use an invented language would be to keep those without "expert" knowledge out of the topic of conversation. Say for example, if you and a friend wanted to talk about a forbidden subject, you could use "op-talk" (assuming none of the others around you knew about it!) to communicate. Of course, the aforementioned examples aren't too difficult to crack, and thus one might move onto something more complex.