As a rough guess:

<li><span class="first">Extremely</span><span class="second">Unwieldy</span></li>

li .first {
display: block;
text-align:center;
}
li .second {
display: block;
text-align:center;
}

dc

Well, DC, you've solved the "extremely unwieldy" part -- the two words do indeed sit above one other centered. And thank you for that. The challenge now becomes, how do you get Orange and Blue and Purple and Green to sit either side of "Extremely Unwieldy" in a horizontal nav -- inline -- and with those four items centered vertically?

How about:

ul { width: 580px; margin: 0px; padding: 0px; list-style-type: none; background-color: #FF9900; height: 50px; }
li { float: left; background-color: #66FFFF; display: block; width: 100px; text-align:center; margin-top: 17px; margin-right: 5px; margin-bottom: 5px; margin-left: 5px; }
li.special { margin-top:8px; }

With

<ul>
<li>Orange</li>
<li>Blue</li>
<li class="special">Extremely Unwieldy</li>
<li>Purple</li>
<li>Green</li>
</ul>

That'll work, you could also do it with line-height and keep the margins the same...

li { float: left; background-color: #66FFFF; display: block; width: 100px; text-align:center; margin: 5px; line-height: 40px}
li.special { line-height: 20px }

Even better :-)

Thank you - much appreciated!

One more question: How do I center the whole thing on the page?

Best way's to put everything into a container and centre that, then everything else you add will automatically be centred too..

body {text-align:center} /* the text-align bits are needed for ie6 */
#container {text-align:left;width: 580px; margin: 0 auto}

<div id="container">
<ul>
<li>Orange</li>
<li>Blue</li>
<li class="special">Extremely Unwieldy</li>
<li>Purple</li>
<li>Green</li>
</ul>
<p>Some content</p>
</div>

One more question. Is there any way to adjust the space between the individual items? Specifically, using the sample given below, there is too much space between "Martins" and "Ride" and between "Ride" and "Sledds & Downhills." Is there any way of reducing this? Thanks.

#nav {font-size: 100%; color: #999; text-align: center; padding-top: 10px; padding-right: 10px; padding-bottom:10px;}
#nav ul {font-family: Tahoma, Geneva, sans-serif; width: 950px; margin: 0px; padding: 0px; list-style-type: none; background-color: #fff; height: 50px;}
#nav li {float: left; background-color: #fff; display: block; width: 100px; text-align:center; margin-top: 17px; margin-right: 5px; margin-bottom: 5px; margin-left: 5px;}
#nav li.special {margin-top:8px;}
#nav li a {text-decoration: none; color:#000;}
#nav li a:hover {color:#666;} #nav li a:visited {color:#000;}

<div id="nav">
<ul>
<li><a href="javascript:;">Regal</a></li>
<li class="special"><a href="javascript:;">Sevens Awilde</a></li>
<li class="special"><a href="javascript:;">Documents Delivered</a></li>
<li><a href="javascript:;">ABCD/AB/ABC</a></li>
<li><a href="javascript:;">Martins</a></li>
<li><a href="javascript:;">Ride</a></li>
<li class="special"><a href="javascript:;">Sledds & Downhills</a></li>
<li class="special"><a href="javascript:;">Reckles Motivees</a></li>
</ul>

It's because you've got a set width of 100px in the #nav li so there's a bigger gap next to smaller words, you can take out the width and replace it with left/right padding for the gaps though this means you'll have to put a line break in for your double line menu items...like so...

#nav {font-size: 100%; color: #999; text-align: center; padding-top: 10px; padding-right: 10px; padding-bottom:10px;}
#nav ul {font-family: Tahoma, Geneva, sans-serif; width: 950px; margin: 0px; padding: 0px; list-style-type: none; background-color: #fff; height: 50px;}
#nav li {float: left; background-color: #fff; display: block; padding: 0 5px; text-align:center; margin-top: 17px; margin-right: 5px; margin-bottom: 5px; margin-left: 5px;}
#nav li.special {margin-top:8px;}
#nav li a {text-decoration: none; color:#000;}
#nav li a:hover {color:#666;} #nav li a:visited {color:#000;}

<div id="nav">
<ul>
<li><a href="javascript:;">Regal</a></li>
<li class="special"><a href="javascript:;">Sevens <br />Awilde</a></li>
<li class="special"><a href="javascript:;">Documents <br />Delivered</a></li>
<li><a href="javascript:;">ABCD/AB/ABC</a></li>
<li><a href="javascript:;">Martins</a></li>
<li><a href="javascript:;">Ride</a></li>
<li class="special"><a href="javascript:;">Sledds & <br />Downhills</a></li>
<li class="special"><a href="javascript:;">Reckles <br />Motivees</a></li>
</ul>

sQ

Belatedly but sincerely, thank you!