Это близко: http://jsfiddle.net/8RuB6/1/
Протестировано в IE9 и последних версиях Firefox, Chrome, Safari, Opera.
HTML:
<span class="tooltip">Hover me</span>
CSS:
.tooltip {
position: relative;
display: inline-block;
font: 13px sans-serif;
height: 60px;
line-height: 60px;
border: 1px solid #444
}
.tooltip:hover:before {
content: 'Add new authorisation';
position: absolute;
z-index: 1;
top: 50%;
margin-top: -15px;
left: 100%;
margin-left: 20px;
height: 30px;
line-height: 30px;
padding: 0 9px 0 3px;
white-space: nowrap;
color: #fff;
font-weight: bold;
-webkit-border-top-right-radius: 5px;
-webkit-border-bottom-right-radius: 5px;
-moz-border-radius-topright: 5px;
-moz-border-radius-bottomright: 5px;
border-top-right-radius: 5px;
border-bottom-right-radius: 5px;
background: #3b679e; /* Old browsers */
background: -moz-linear-gradient(top, #3b679e 0%, #2b88d9 50%, #207cca 51%, #7db9e8 100%); /* FF3.6+ */
background: -webkit-gradient(linear, left top, left bottom, color-stop(0%,#3b679e), color-stop(50%,#2b88d9), color-stop(51%,#207cca), color-stop(100%,#7db9e8)); /* Chrome,Safari4+ */
background: -webkit-linear-gradient(top, #3b679e 0%,#2b88d9 50%,#207cca 51%,#7db9e8 100%); /* Chrome10+,Safari5.1+ */
background: -o-linear-gradient(top, #3b679e 0%,#2b88d9 50%,#207cca 51%,#7db9e8 100%); /* Opera11.10+ */
background: -ms-linear-gradient(top, #3b679e 0%,#2b88d9 50%,#207cca 51%,#7db9e8 100%); /* IE10+ */
filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#3b679e', endColorstr='#7db9e8',GradientType=0 ); /* IE6-9 */
background: linear-gradient(top, #3b679e 0%,#2b88d9 50%,#207cca 51%,#7db9e8 100%); /* W3C */
}
.tooltip:hover:after {
content: ' ';
position: absolute;
top: 50%;
margin-top: -15px;
left: 100%;
margin-left: 20px;
width: 21px;
height: 21px;
background: #ccc;
-webkit-transform: rotate(45deg);
-webkit-transform-origin: 0 0;
-moz-transform: rotate(45deg);
-moz-transform-origin: 0 0;
-o-transform: rotate(45deg);
-o-transform-origin: 0 0;
-ms-transform: rotate(45deg);
-ms-transform-origin: 0 0;
transform: rotate(45deg);
transform-origin: 0 0;
background: #3b679e; /* Old browsers */
background: -moz-linear-gradient(left top, #3b679e 0%, #2b88d9 50%, #207cca 51%, #7db9e8 100%); /* FF3.6+ */
background: -webkit-gradient(linear, left top, right bottom, color-stop(0%,#3b679e), color-stop(50%,#2b88d9), color-stop(51%,#207cca), color-stop(100%,#7db9e8)); /* Chrome,Safari4+ */
background: -webkit-linear-gradient(left top, #3b679e 0%,#2b88d9 50%,#207cca 51%,#7db9e8 100%); /* Chrome10+,Safari5.1+ */
background: -o-linear-gradient(left top, #3b679e 0%,#2b88d9 50%,#207cca 51%,#7db9e8 100%); /* Opera11.10+ */
background: -ms-linear-gradient(left top, #3b679e 0%,#2b88d9 50%,#207cca 51%,#7db9e8 100%); /* IE10+ */
filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#3b679e', endColorstr='#7db9e8',GradientType=0 ); /* IE6-9 */
background: linear-gradient(left top, #3b679e 0%,#2b88d9 50%,#207cca 51%,#7db9e8 100%); /* W3C */
}