Other fun household items which will fluoresce under UV light:

Your feet (athlete's foot) and sometimes hands.

Banana "mold" (the black spots' edges).

Your credit cards and IDs (usually a bird on VISA and "AMEX" on so-named).

Money (embedded denomination "strip" is different for each modern bill).

Centipedes and Scorpions (seriously, just go into your yard at night and scan the ground for wigglies).

If you have beehives, the Varroa Destructor (species/pest) also shines brightly on their little carapaces.