I was looking through the internet when I saw that this past weekend in London they had the first ever BBC Sherlock Homes Convention. This convention had various stars from the show including Sherlock himself Benedict Cumberbatch. The fans came as from as Chile to see the stars. You can read it here.
What amazed me was the price on the tickets. On a one day ticket standard admission was 29 pounds or $43.79 which got you in to the convention, see the panels and stand in line for autographs from some of the stars. Then there are other admission prices that allow you more benefits. You can set them here.
http://www.sherlocked.com/index.php/tickets
The highest level was platinum. This level allowed you get your picture with all the stars, their autographs, preferred seating at all the panels and various pieces of merchandise. The price for this level was 2995 pounds or $4552.40! You can see the list of goodies here.
http://www.sherlocked.com/index.php/tickets
The Platinum package has to be the highest I have seen for any comic book or media convention.
A final note the conversation rate I used was $1.52 which is the best rate at this time.