Besides the typical small entry in a group print ad on Sunday morning and directional signs posted same day, what have your REAs done to drive traffic into your open house?
Craigslist! I do side work for an agent in the RE office where I work at the front desk by making flyers and posting her listings weekly on Craigslist. When she has an open house I always include that in the header on Craigslist. She has mentioned that people going to her open houses have told her that they saw it on Craigslist.