Apple actually has an embarrassingly straightforward implementation of a CSS3 clock on their ipod nano page:
-moz-transform: rotate(%ddeg)
.hand {
-moz-animation-direction: normal;
-moz-animation-duration: 60000ms;
-moz-animation-iteration-count: infinite;
-moz-animation-name: spin;
-moz-animation-timing-function: linear;
}
.hour.hand {
-moz-animation: 0s ease 0s normal none 1 none;
}
.minutes.hand {
-moz-animation: 0s ease 0s normal none 1 none;
}