How do you deal with trolls?

I know there have been many questions concerning trolls, but I would like to know how you personally deal with them.

Do you feed them?
Flag them?
Ignore them?

I had my first experience modding a troll the other day during my husband’s radio show. I didn’t boot the troll until several viewers asked me to. At what point do you say “enough is enough”?

@mods I would love to hear from you!