I do (yes even as a mum and wife) and although I don't write in it as much as I did when I was 15, it still contains almost all my secrets and important events! Other than my bestie and hubby, it was the first to know I was pregnant :-)
I was reading through my teenage diary last week, and it was all about my friends and boys. Love it. For some reason I blacked out some bits that I obviously didn't want my adult self to read (lol).
Anyway the reason I brought up diaries is, when Melissa and I decided to write our book Forbidden Territory, we got to know our characters by getting them (Mica and Lexy) to write in their diaries. Not only was it super fun, but it totally helped us learn who the girls were, what they wanted out of life and how they thought.
What sort of things do you tell your diary? And, do you think some day, if you have kids, you'll let them read your diary? I'm still undecided!