I get a slow trickle of enquiries from it but you don't need that many for it to pay dividends. Some of the enquiries have been NVA (No Viable Access) so I have turned them down. There have been a few one offs as well. Also, there have been some enquiries where I haven't heard any more about it (presumably they got someone cheaper).
I currently have work from it for £1,300 a year if I were to keep to schedule. That's from being on it two years for £98. So I reckon it's been a reasonable investment.
Not spectacular but it has been worth doing.
In the area that I cover, there actuqally is a window cleaning company called Window Washers which sometimews can cause confusion. I have had people phone up for the other company. A couple of times I have got jobs this way. I've been honourable about it though. I've never pretended to be the other company.