speaker cone dust brush or cleaner

I could reaaly use a dust brush for speaker cones. Any recomendations?

And since I started a new topic I thought it would be worthwhile to ask about liquid cleaners as well, even though I do not have any need for them.
how about either a soft paint brush or a can of compressed air ?
Id just let it go, its not likely to effect the sound unless its caked on.
Dnewhous: I have wondered about this myself, and I contacted my speakers manufacturer about it. He said just leave it or use a lightly damp cloth. BUT, that would be only for cosmetic reasons.