I'd say the following:
i think the most popular thing is the games
the most popular thing on earth is a Jackson everybody has one
Some popular innovations include sugar for tea, cotton underwear, tourism, science fiction, detective novels and uppward mobility. The MOST popular thing, however, was probably thet same as the most popular thing today.
It,s the most popular thing in the world.
most people were wearing mask and the most popular thing was a princess
The most popular thing to have is technology it self which includes ipads, ipods, iphones, netbooks, cellphons and new automobile
Thor and his hammer
A bus tour
it is what ever you want it to be