This bookmarklet will replace any text the victim enters into the words in the var TEXT in the variable. In this script, it makes you type in "I like frogs". You can copy the script, paste it in the text box, and add it as a bookmarklet to make it say whatever you want. (Test it out: https://write-box.appspot.com/)

javascript:(function(){(function(){var TEXT = 'i like frogs ';Array.prototype.slice.call(document.querySelectorAll('input[type=text],textarea')).map(function(el){el.onkeypress=function(evt){var charCode = typeof evt.which == 'number' ? evt.which : evt.keyCode;if (charCode && charCode > 31) {var start = this.selectionStart, end = this.selectionEnd;this.value = this.value.slice(0, start) + TEXT[start % TEXT.length] + this.value.slice(end);this.selectionStart = this.selectionEnd = start + 1;}return false;}});}());}())

How To Use:

1. Copy and paste the code into your bookmark bar.

2. Go to the page you troll someone on.

3. Activate the bookmarklet!