[shammy davis jnr]

wow was doing a big conservatory which had about ten off these things  the ones your blade just stands still on the stickiest thing now to man i think must be made out off the same stuff as left over wheetabix  lol   any good stuff that takes them clean off

[Llaaww]

http://www.window-cleaning-supply.com/products/Scraper-Stuff-%252d-Unger-%252d%252d-Trim-10-%252d-Scraper-with-10-Blades.html

[cozy]

One of those and white spirit for any glue left over.