This weekend I attached clips to the trunk cover that hold an umbrella on the underside; those being a relative necessity in Washington state. Picked up the clips on Amazon for fairly cheap at $20. They are advertised as being for the Accent and Veloster. I found the posts a little shorter than I may have liked, but the metal fasteners had enough to hold on to to keep the clips in place.
Trunk Cargo Clip HolderHYUNDAI Accent Veloster : Amazon.com : Automotive
Oh, and the umbrella in question, heh...
ThinkGeek :: Blade Runner Style LED Umbrella
Here's a view through the window:
A view of the fasteners. I had to color them black to better match the cover since they were a standard aluminum/metal color:
And a view inside the trunk: