12:00 shows a 'P'
03:00 shows a 'e'
06:00 shows a 'r'
09:00 shows a 'l'
small striding camel in the center

Potential taglines:

Oh, look, only eighteen seconds until I start coding Perl again!
When is it _not_ perl time?
I'm sorry, I have to leave, it's Perl o'clock.
Did you say something? I didn't catch a SIGINT.

I'm sure there are others...