How many languages can fit into a brain?

Come on, there must be a ceiling on the amount of languages a person can learn. Surely there are only so many words that can be crammed in there before one of several eventualities is reached:

1) There are so many languages in there that the wires are all entagled and cross talk starts occuring. A person might be speaking Icelandic and suddenly a Hungarian word will spill into a sentence, the speaker simply unable to segretate languages into their own orderly closed off sections anymore, to the confusion of many listeners.
2) Old languages are simply overitten.
3) Worst case scenario. The head and mouth begin involuntarily word hemorrhaging. Kind of like sterotypical Tourette's, but not necessarily shouted, and not only profanities. In severe cases a mouth bottle-neck will occur and words will start coming out of the persons ears.

Do you think there is a limit on the amount of languages a person can retain and use functionally? Where do you think the ballpark is? Who knows the Guinness record for most languages spoke?

Jam it back in, in the dark.