Vileda Windomatic Window Vacuum £19 @ Tesco instore only.
Lightweight and with an ergonomic grip for comfortable handling, the Vileda Windomatic cordless window vacuum cleaner is a quick and easy way to a streak-free finish. It is ideal for washing windows, removing condensation, wiping mirrors and cleaning up spills. The combination of a wide wiper blade and efficient suction power effectively removes water from windows without drips or the need to polish afterwards. A flexible head gives you an optimum cleaning angle, allowing you to vacuum right down to the base of the window and into corners. Powered by a mains rechargeable lithium-ion battery, the Vileda Windomatic can wipe up to 60m² on one full charge.
Got mine in Sunderland so not sure if national.