What do you think of them? Are you scared shitless of them like most people or are you like the one person who can stand them? I personally hate clowns and mannequins but I love ventriloquist dummies. They're creepy cool.
I love clowns... if they have original material. The circus that comes to town every year has used the same clown acts every year for the last four or five years. I've lost count. If they have fresh material, they're hilarious, and I have absolutely no idea how people could possibly find these delightful comedic experts to be creepy.
Ventriloquism... well, one of my favorite comedians is Jeff Dunham. Haven't been able to find any other ventriloquists to be entertaining, though.
I've never seen the kinds of mannequin's you're talking about; at least, not outside of cartoons. The only mannequins I know of are the ones that display clothing in the windows of shops at the mall.
clowns are nice & funny but ventriloquist dummies have a super super scary face & it kinda of look real too & that makes it a lot more scary & in lots of show they always evil