Dubai for 8 hours

Dear all,

can you give me any ideas what a person can do in Dubai for 8 hours - from 3pm. until 12am. I am landing at Dubai airport at that time and have to wait for my next flight, so I want to see sothing from Dubai. Any ideas? Sightseeing buses and how can I get there from the airport?
I heard something for a night sighseeing bus from 7.30 to 9.30pm. Anyone has tried it? and when does it departure from?

thanks a lot

xx