Received fonts exclusions list

[Durandal]

This is probably just a bit too much for a feature request, but I was wondering if it'd be possible to add a list of received fonts you'd like to display or not display. For example, when I talk with my co-developer on Adium about our software, we'll send each other snippets of code, for which the code plug-in comes in very handy. I'd like to keep regular messages in the font I specify, but if one of his messages comes through with the Courier font, then I'd like Adium to display it.

Does this sounds reasonable?

EDIT: This could also come in handy for those people who absolutely hate certain fonts, like Sand and Comic Sans.