I know it’s totally stupid and you normally really shouldn’t use tables when not creating tables, but:
Table cells can align multiple lines of text vertically centered and even do this by default. So a solution which works quite fine could be something like this:
HTML:
<div class="box">
<table class="textalignmiddle">
<tr>
<td>lorem ipsum ...</td>
</tr>
</table>
</div>
CSS (make the table item always fit to the box div):
.box {
/* For example */
height: 300px;
}
.textalignmiddle {
width: 100%;
height: 100%;
}
See here: http://www.cssdesk.com/LzpeV