<p>Most of what grads have, undergrads have too. Stanford realizes that many of its undergrads are capable of graduate-level work–which is why most grad courses are open to undergrads as well (there are certain sections in department course listings that are supposed to be exclusively for grads, but advanced undergrads can take those too; and there are usually whole sections of courses for undergrads and grads).</p>
<p>As for SLAC, I know undergrads can intern there.</p>