When I'm psychotic I have a particular morbid fascination with numbers... 10 means a death and the possibility of a new birth, 3's are about killing. 4 is the cross with no spirit. 5 is the cross with spirit (no I'm not normally religious). 00 is about starting over... 9's are powerful.

I will read the numbers from the http line in chrome and think they have meaning, or I'll translate letters into numbers and get meaning from that. Or count the number of letters and words in a message and so on...

This only started a few years ago.

You can read about Daniel Tammet, who has a condition called synesthesia. He sees numbers as coloured landscapes and relates emotionally to them and uses that to do all kinds of mathematical operations in his head as well as memorize pi to over 20K digits.