Bay seniors and their grandkids with a taste for things scientifically bizarre will get a major kick out of Eyelusion, an Airstream trailer refitted with more than a dozen brain bending exhibits involving mirrors, kaleidoscopes and other low, low tech devices. This one room museum is for hire only. For prices and availability you’ll have to view their website. Another goofy idea for outcdoor parties is to rent a Ben & Jerry’s ice cream truck. Macy’s is the place to contact them at 415-533-4588.