Magnetic window squeegee thingy that cleans the outside of windows without having to go up a ladder??

[iwouldgoouttonight]

Has anyone ever used one of these? Are they any good and do you know where you can buy them from?

ebay- i want one as well! there are cheaper versions but only the most expensive ones work on double glazing!

i got mine from pitch tv i think they have a website i paid about 30 with delivery not used them yet tho

Do they work well?

Has anyone actually used one? We've got double glazing so don't want to spend loads if they don't work very well!