Does nobody play games anymore? How about charades? Have a jigsaw puzzle set up in a corner with chairs where people can come and go as they please. You'll be suprised how many times they will venture over to the table.
Give everyone who enters your house three marble. ONLY THREE. Now...the result is to collect as many marbles as you can during the visit. So...the rules can be something like
1) Everytime you see someone cross their legs, you can tell them to give you one of their marbles. They have to give it up.
or
2) Everytime you hear somebody say ____(you fill in the blank) you can tell them to give you one of their marbles...
the person with the most marbles at the end of the visit, wins something. It can be something trival, something great, or it could even be something that could be passed around each year to the NEXT winner. Like a tradition! We use to have a "worthless award" trophy. Every year somebody won it for being the most worthless during the summer. We had a summer celebration at the end of the season, and people go up in front of the crowd of about 20 or so and told why they were the most worthless. It was a hoot! The trophy was then awarded, and the new winner's name and date actually put on there...till the next year.
MAKE A MOVIE...take someone's video camera and during the entire visit, have someone there video it. It's great fun.
Just a few ideas...
JJ