Oh yeah, we did. We spent a Saturday making Lego miniman heads for our annual neighborhood Halloween party. Those are hours we will never retrieve.
But of course it was worth it. We bought concrete form tubes (also called Sonotubes) at the hardware store: 10″ diameter for larger grown-up noggins, 8″ inch diameter for kid craniums. We sawed the tube into individual helmets, then traced cardboard circles for the tops. We used sponge for the “connectors.” And spray-painted the whole deal bright Lego yellow.
We skipped the rest of the costume because, even though we made an effort, we weren’t going to go overboard on effort. (Here is a link to some folks who went above and beyond in making Lego costumes.) The Lego miniman smirk was the best part of the helmet, I think. The worst parts: no peripheral vision and gradual, but undeniable, aphyxiation. Happy Halloween!