You could add a description to each combo item to make it more descriptive. In addition, you could assign an image to each combo item.

<combobox>
    <comboitem label="Simple and Rich" image="/img/coffee.gif"    
    description="The simplest way to make Web applications rich"/>    
    <comboitem label="Cool!" image="/img/corner.gif"    
    description="The coolest technology"/>    
    <comboitem label="Ajax and RIA" image="/img/cubfirs.gif"    
    description="Rich Internet Application by Ajax"/>    
</combobox>

Like other components that support images, you could use the setImageContent method to assign the content of a dynamically generated image to the comboitem component. Refer to the Image section for details.