border-radius:30px; -moz-border-radius:30px; -webkit-border-radius:30px; for ie 6-8 use http://css3pie.com/ or http://www.modernizr.com/
I use this often in ClickBump Engine templates... .rounded { border:1px solid #ccc; border-radius:12px; -moz-border-radius:12px; -webkit-border-radius:12px; padding:10px; } <div class="rounded">This element will have a 1 pixel gray border with 10 pixels of padding applied between the text and the inside border</div> HTML:
Latest webkit and ie9 support native border-radius, so there's no need for -webkit-border-radius anymore. Visitors will thank you for NOT putting kB of javascript hacks just to get rounded borders on ie6.