Anything fun. At all.

Pre-cut melons - melons are particularly prone to having listeria live on the outside of them, this is then transferred to the inside when they are cut, and the bacteria multiply when they're stored. So I only eat fruit within four hours of it being cut, and only if I've done it myself, because you don't know who's using what knife and how long the fruit has been stored.
Same goes for salad that anyone else has prepared.

Shellfish - oysters, mussels, prawns.
Deep sea fish - check out the guidelines. High mercury stuff once a fortnight only.
Salami, and something about luncheon meats? (I dunno, I'm vego so don't really pay attention)

Praise 97% fat-free mayonnaise is completely animal-product free, so should be safe :-)