Of course, my mother and my best friend Amanda are the only two I usually show my silly side to. When my mom is feeling sort of depressed I tend to do lots of goofy things to make her smile.
One day about five years ago she came home from work and had a horrible day, she sat down in the chair and was really quiet and moody all evening. So I grabbed the make up and a pair of felt reindeer antlers on a headband, painted my face up like Rudolph the red nosed reindeer, and went prancing around the room singing the song in a funny voice.
She always cheers up when I do such things, I know to anyone else I'd look like I was making an utter fool of myself but if it makes my mother smile the haters can go suck on lemon juice ice cubes. >=3
It depends on one's definition of "silly". I have been asked if I was the Doctor's "other daughter" because of my verbal piffle, but my mind is usually living on another plane of existence, so a lot of things come out as being silly and irrelevant to the reality I'm occupying.
I try to be quieter about it around strangers and while employed, as it tends to scare people into thinking that sanity is optional to function. (The psych evaluations say I am sane, which surprised me.)
Otherwise, friends, classmates, and family know that the caustic commentary, random trivia, and weirdness will fly at any moment.