There are many different ways you can alter text and images with Font Effects.
For example:
Change the color on mouse over.
Change the font on mouse over.
Change the size on mouse over.
Create a glow effect on mouse over.
Create a drop shadow effect on mouse over.
You can even have them work in combination:
Fly in from the right, then display a glow effect on mouse over.
Fade in, then change the color on mouse over.