My first 3 choices were 512, 420, 187.
512 because I live in Austin, and the others just because of pop culture.

Unfotunately there was a race weekend a couple days after my app was submitted, so the numbers were taken.
My second three were 969, 696, 599. The first Two just because of the flip-flop numbers, 599 for the cc's of my bike.

599 was the only one available.