At a couple of weddings I've seen people put up signs saying "please be safe. If you don't have a designated driver, call Suchandsuch Taxi at 206-NNN-NNNN". Anyone else done/is doing this? Do you have to call the cab company ahead of time and say "we may need a number of cars from this location at any point between 8pm and 11pm"?

1st year anniversary in Victoria with a killer whale topiary!