<svg>
<defs>
<filter id="f1" x="0" y="0" width="1" height="1">
<feImage xlink:href="#p1" result="p1"/>
<feImage xlink:href="#p2" result="p2"/>
<feBlend mode="multiply" in="p1" in2="p2" />
</filter>
<path id="p1" d='M100 100 L200 100 L200 200 L100 200 Z' fill='#00FFFF'/>
<path id="p2" d='M150 150 L250 150 L250 250 L150 250 Z' fill='#CC3300'/>
</defs>
<rect width="100%" height="100%" filter="url(#f1)"/>
</svg>
Also see: Tab Triggers