Hexadecimal would be better, better you can tweak the colour to suit your purposes much more precisely

<table cellpadding=10><TR><TD style="filterLOW(color=#ffff33, strength=15)">
<B><FONT SIZE="+1" COLOR="#ff0000" FACE="Comic Sans MS">How do you mean different fonts?</FONT></B></TD></TR><TR><TD style="filterLOW(color=#3333ff, strength=15)"><FONT SIZE="+3" COLOR="#00ff00" FACE="Brush Script MT"><B>I don't see why not, just change the font face like you normally do </B></FONT></TD></TR><TR><TD style="filterLOW(color=#ff3300, strength=15)"><FONT SIZE="+1" COLOR="#3300FF" FACE="Times New Roman"><B>Though it appears you have to do it in paragraph chunks, it doesn't seems to work for individual letters </B></FONT></TD></TR></table>

Don't go over the top with it, it makes it fairly hard to read without enlarging the text