Some banknotes in my collection – I believe all of these are still available for purchase online at very reasonable prices.
Libya’s 1 dinar banknote, issued in the 1980s, with Muammar Gaddafi on the obverse. Apart from this, the other banknote featuring Gaddafi is the 50 dinar bill. After the 2011 revolution with overthrew him, Libya’s Central Bank Governor is redesigning new banknotes that will likely replace Gaddafi-emblazoned bills. On 20th October 2011, Gaddafi was captured alive, beaten and killed by NLA fighters:

Iraq’s 25 dinar banknote, issued in 1986, with Saddam Hussein on the obverse. Apart from this, there are many other banknotes featuring him. After the deposition of Saddam in the 2003 invasion of Iraq, the Iraqi Governing Council and the Office for Reconstruction and Humanitarian Assistance issued new notes, understandably none of which featured Saddam. He was captured in December 2003, and was hanged on 30th December 2006:

In one of the worst cases of hyperinflation the world has ever seen, the Reserve Bank of Zimbabwe introduced trillion-denominated notes on 16th January 2009, including the incredible Z$100 trillion banknote. In mid-January 2009, Z$1 trillion was equivalent to USD1. Forbes Magazine reportedly mentioned that by December 2008, inflation was estimated at 6.5 quindecillion novemdecillion percent (65 followed by 107 zeros):

North Korea’s 100 won banknote, issued in 1992, with Kim Il-Sung on the obverse. Apart from this, the other banknote featuring Kim is the 1,000 and 5,000 won bill:

Hungary went through the worst case of hyperinflation in history between the end of 1945 and July 1946. In 1944, the highest denomination was 1,000 pengo. By mid-1946 the highest denomination was 100,000,000,000,000,000,000 pengo. At its worst, prices doubled every 15 hours. In Zimbabwe’s hyperinflation, prices doubled every 24 hours. The banknote I have below is that of a 1 billion pengo (10 to the power of 9 pengo), issued in May 1946 and withdrawn a mere 2 months later. This is not the biggest ever Hungarian banknote of that period: that’s the 10 to the power of 20 and 21 b-pengos. I am still looking for reasonably priced banknotes of those:
