Of note is the fact that Swaziland's one Lilangeni coin is minted from the same blank as the Pound. What this means is, the shape, color, and weight of the coins are virtually identical, and what THAT means is that you can usually pass off one for the other. In fact, much in the same way that US residents will occasionally receive a Canadian dime rather than one of their own, as change, UK residents will occasionally receive Lilangeni coins.
And why, pray tell, is that, given that the UK and Swaziland are separated by about a third of the globe? Simple! As of today (February 23, 2002), the exchange rate is about 16 to 1, in favor of the Pound. So if you ever travel between the two, why not recoup some of your costs by bringing back a sack of Lilangeni coins, and making all your future vending machine purchases for next to nothing?
Isn't fraud fun?