Silly things to do in public

[Redwallfan7]

spray silly string everywhere that you go in public

[SpiderMonkey]

Cover the floor in marshmallows, then light them on fire. 

[W0NWILL]

Sing. Especially if you're me and have a terrible singing voice.

[Redwallfan7]

Lol

[Rainshadow]

  When you hear a song you like on the radio in a store or something, just start dancing!  Feel free to do crazy moves.

[Tiria Wildlough]

Get people to sing 'Stronger' by Kelly Clarkson, with you, like in the music video.

[Rusvul]

wear rags and play a fiddle and sing songs like you are a bard in the medevail times.

[Rainshadow]

  Take out a bagpipe and start playing tunes.  Preferably It's a Small World.  It doesn't matter if you're good at all.

[Redwallfan7]

Wear a Scottish outfit and play bag pipes in public, and speak in a high land accent

[Rainshadow]

  Put on dark shades, a black fedora, black trench coat, black shoes, black everything, and go walk in public.  Do not speak to anyone.  Try to hide your face.  Creep others out!

[AxeHound]

Walk up to people you don't know and pretend you know them.