What's a reasonable consequence for being rude?

I'm working on fine tuning some household rules. My kids have been getting by with some snotty talk, extremely negative talk and fake cursing (freakin, bullshizzle). I ended up with a long list of difficult to remember rules, so I'm consolidating it into one rule: Speak nicely. Now I need a logical consequence to breaking this rule. I definitely think they should apologize, but I also want something that will actually deter them. Any suggestions? (They are 13 and 8)