I don't know the origins of this practice, but messages of sympathy on blankets and towels are a common sight at funerals here in SG. The banners would be hung up at the wake and then distributed amongst family members after wards for daily use. This long banner is made up of thin striped terry towels tacked together side by side. In fact, this banner got so long it had to be hung on the row of trees in the carpark next to the wake located at a HDB block's void deck.
You can even order these traditional funeral blankets online! This one has a GREAT tag line:
Funeral Blankets - Get your loved ones covered.