This plugin is the most advanced of it's kind as it not only has full support for the placeholder value but it also allows you to set a custom style when the text inside the text field is the placeholder so it can truly look and act like the placeholder in HTML5.

Ever need to know what the new line character is on the client side? Have you, like I have, tried to find the perfect way to add a new line in a PRE tag, so that it did not add a leading or trailing space? Have you tried to figure out what new line character is being used in a textarea for those new lines? Finally you can easily figure it out. Thanks to the new $.support object, it can be tested once an never worried about again. This extension, when included, will automatically extend the $.support object with the appropriate tests results for the client browser. Then later in your application you can test against those results to find the proper new line character for the OS browser combo for the client.

Usage:

$(function() {
var EOL = false;
if ($.support.rnNewLine)
EOL = "\r\n";
else if ($.support.rNewLine)
EOL = "\r";
else if ($.support.nNewLine)
EOL = "\n";
else