Pirate Riddle

Here's a fun little brain teaser courtesy of Espn's Page 2. (don't bother following the link - they don't tell you the answer - you have to figure it out on your own).

There are five pirates in a boat, with 100 pieces of gold to divide among them. They decide to divide the gold by the following methodology:

The smallest pirate will distribute the gold, and then each pirate will vote on the distribution. If the smallest pirate gets a clear majority (including himself) to agree on his distribution, then that is the way the gold will be divided. If not, he is thrown overboard and the next smallest pirate will re-divide the gold among the three remaining pirates. They all then vote again with the exact same conditions (acceptance requires a majority, lack of acceptance implies the pirate who divided the gold is thrown overboard and the next smallest pirate takes his place as gold distributor). Each pirate will only accept that outcome that guarantees him the most gold he will get under any scenario. No other consideration can trump that.

The question is this: How many pieces of gold can the smallest pirate keep and remain in the boat?
.