Chocolate is the best bait - a small piece of Dairy Milk is ideal.
The trouble with the slicing variety of trap is that it can make a bit of a mess. Back when I was an impoverished student we caught one in the grill pan (it was one of those very old gas cookers with a high level grill, I can't remember what possessed us to put a trap in there - footprints in the grease probably, we were an all male household and tended to save up washing up for the week until astonishingly good natured girl friend turned up Friday night and cleared it
). It did a very messy decapitation job and resulted in a surprisingly large pool of blood in the bottom of the pan. We got a cat after that, but like all cats she hated being left out of things; the first time we had a party she brought home a mouse and literally disembowelled it in the middle of the dance space. It's not easy trying to simultaneously (1) scoop dead mouse off floor without dropping any more entrails or spreading them any further across the floor than they are already (2) fend off cat that's bitterly opposing attempt to deprive her of her victim and (3) fend off hysterical party goer trying to step on cat to stop her grabbing the mouse again.
Our current cat (who probably thinks her name is "Stupid Cat") has always, without fail, responded to every domestic crisis or excitement by adding a live mouse or bird to the situation. She once dropped a live sparrow in the kitchen just before an NCT coffee morning; it shot straight under the fridge freezer. I cleared off to work and left them to it
. Adding weight to the saying that if you want something doing you should ask a busy woman, the pregnant women pinned the cat down, hauled the fridge freezer out of its niche and shooed the bird out in about five minutes flat. It would have taken me hours...
Thankfully, when she brings rats home she always kills them (she had three in one day once). Frogs are probably worst, they make the most horrible, unearthly noise when she catches them. Apparently the very worst thing a cat can bring home is a live weasel - the smell is unbelievable and they're extremely vicious. I don't think we've got any urban weasels here though.