HughMartin.....
Similar 'crisis' this afternoon. Rushed out, purchased and can vouch for the following product. Available various places; cheapest PC World & Dixons: £4.99.
That said, I'm wary of tissues, they being (albeit slightly) abrasive if used hard; so elected for
very gentle run over to get the cleaning fluid on the screen, followed by a light polish with brand new duster (have to be quick before it evaporates). Screen now genuinely 'as new'.