I found this advice from Martha Stewart for a wedding party:
"Just as the coffee is being served, the dancing always seems to begin in earnest, leaving guests with cold coffee when they return to the table. At your reception, offer caramel wafers to rest across the top of the cup -- the coffee will stay warm and the caramel will soften, turning the wafer into a sweet gooey treat. To prevent premature nibbling, the wait staff should let guests know what the wafers are for when they first bring out the coffee". Surf for more information to: http://www.marthastewart.com/portal/site/mslo/menuitem.0e0eb51a2e6b5ad593598e10d373a0a0/?vgnextoid=474d365095043110VgnVCM1000003d370a0aRCRD&autonomy_kw=caramel%20wafer