When my kit arrived I'd looked at the 5 digit list and set my heart on one particular number. Closer to the end of my build I looked again and that one had been taken so I had to have a rethink.
I considered using my birth date but it didn't look visually appealing. I have always liked Ambigrams so I decided on something with a rotational symmetry.
Since Bill & Ted's Excellent "Sixty-Nine Dude!" makes me laugh (coupled with the fact I'm a bit of a cheeky chappie) the number I picked, and was subsequently issued with, fits me perfectly.
Si.