I noticed some of our chilli plants were looking like they had been nibbled by something. I had a quick look over the leaves a few days ago, but couldn't find much. The plants look much worse today so I started turning every leaf over - only to find cabbage white caterpillars!
If they start on mine there will be mass murder... you should see how many have died on the sacrificial Nasturtiums... :-X
They certainly have a taste for them, as they have made neat work of the chillies in our conservatory. We must have had a butterfly come in through the patio doors...