How to create hoverover popups in Rails 3.1

Use some CSS and Javascript!

Here's an example you can play with: http://jsfiddle.net/cdpZg/

Copying it here, just in case.

HTML:

<div id='user'>I am a user. Move your mouse over me</div>
<div id='popup'>Extended info about a user</div>
<div>I a piece of useless information. No use hovering over me.</div>

CSS:

#popup {
    height: 50px;
    width: 200px;
    text-align: center;
    vertical-align:middle;
    background-color: cornflowerblue;
    color: white;
    display: none;
    padding-top: 8px;
    position: absolute;
}

Javascript:

$(document).ready(function() {
    $('#user').hover(function() {
        $('#popup').show();
    }, function() {
        $('#popup').hide();
    });
});

Just set the title on your link like this

<a title="Some text that will show up when I hover over this link">My link</a>