Dealing with Solicitors

We've had our fair share of solicitors coming up our walk and trying to sell everything from tree care to Bibles to wrapping paper. Some of the solicitors we don't mind so much (Girl Scouts, your cookies are always welcome), but others we find downright annoying. Some of our neighbors have started to put up No Solicitors signs around their front doors, but we're thinking that a plan like that might backfire, so we just ignore the doorbell when there's a solicitor. How do you deal with solicitors?

[ Photo from Lana's Blog, No Soliciting Sign from Etsy shop ScribbleIt ]