I just happened to notice that the last 3 episodes (CN's repeats, not Fox's "last 3 episodes", which seem to span the last 2 years) have direct jokes about Leela's depth perception problem... nothing big, but...
A Bicyclops Built For Two: "How far away are they?" "A billion miles?" *BAM* (okay, not Leela specifically, but directly related to her)
How Hermes Requisitioned His Groove Back: "They said I probably shouldn't fly with just one eye..."
A Clone of My Own: Cubert questions Leela's ability to fly a spaceship. Leela takes a swing at him and misses by a good foot.
On a related note, whenever I see "Requisitioned", I get that musical number stuck in my head for WEEKS after. "I am Bender, please insert girder."
fo0bar