It goes without saying that this site constitutes one gigantic spoiler, so don't go there if you are still interested in discovering for yourself anything about Portal 2 or the founder of Aperture Science, whose recorded messages of accelerated dementia have made the character another cult hit from Valve.
"Cave Johnson, Here!" has thus far amassed 39 quotes and will serve them to you at random or in a full catalog. If you have one to contribute, they take submissions.
Cave Johnson, Here! [Site. Thanks Andrew F.]