If you want to attract an attention, you don’t have to scream.
Yes, you don’t have to shout “Here I am, I’m the best”.
Especially when everybody is screaming the same.
Sometimes you don’t have even to speak! Every fool can speak.
The secret is to shine.
And here are amazing guerrilla marketing examples, which are shining so bright, that they don’t need any additional word to be described.