Hee's Forbes Magazine's 2006 list of billionaire rulers. Prince albert made the list this year. I've compiled the list from the slide show and posted an excerpt from the article.
Forbes Billionaires
http://www.forbes.com/2006/05/04/rich-kings-dictators_cz_lk_0504royals.html
Fortunes Of Kings, Queens And Dictators
Luisa Kroll 05.05.06, 9:00 AM ET
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These kings, queens and dictators warrant a separate list from our billionaires, which had a record 793 members this year, because of the difficulties separating their personal fortunes from the wealth of the state. Also, the billionaires' rankings exclude extended family fortunes, and most of these rulers share their fortunes with numerous relatives, like Liechtenstein’s Prince Hans-Adam II, who heads a family fortune that dates back almost nine centuries.
1. King Abdullah Bin Abdulaziz
King/Saudi Arabia $21 billion Age: 82
2. Sultan Haji Hassanal Bolkiah
Sultan/Brunei $20 billion Age: 59
3. Sheikh Khalifa bin Zayed Al Nahyan
President/United Arab Emirates $19 billion Age: 58
4. Sheikh Mohammed bin Rashid Al Maktoum
Ruler/Dubai $14 billion Age: 56
5. Hans Adam II von und zu Liechtenstein
Prince/Liechtenstein $4 billion Age: 61
6. Prince Albert II
Prince/Monaco $1 billion Age: 48
7. Fidel Castro
President/Cuba $900 million Age: 79
8. Teodoro Obiang Nguema Mbasogo
President/Equatorial Guinea $600 million Age: 63
9. Queen Elizabeth II
Queen/U.K. $500 million Age: 80
10. Queen Beatrix Wilhelmina Armgard
Queen/Netherlands $270 million Age: 68