I think it would be nice to have something like:
/dcc -e ignore *.mp3,*.wav
For ignore all except
/dcc -o ignore *.dll,*.exe,*.html,*.htm
For ignore only,
and possibly..
/ignore -d ignore for disable.
Whilst still having functions like:
/dcc ignore [on|off]

Of course this is easily scriptable, but I guess most feature suggestions are..

Not a bad suggestion, though.

Yes I know, but I thought it'd be nice built into mIRC.