My mistake... of course it should be Simon says...
I was listening to an old song by The Prodigy - Charlie - where "Charlie says" is repeated, and I was convinced that this was what actually is "Simon says".
There is an idiomatic use of 'Charlie's...'. When I was at school, a euphemistic way of telling a woman her petticoat was showing under her hem-line was 'Charlie's dead'*. As petticoats are more or less a thing of the past, I heven't heard this used for a good few years.
PS I believe the French equivalent is Tu cherches une belle-mêre? Can someone confirm this (or have I been enduit avec du beurre ;-))?
"Charlie" in reference to an enemy is limited to references of the Vietnam war, I believe. The Viet Cong were often referred to by the abbreviation "VC," which in the phonetic alphabet became "Victor Charlie," and then was eventually shortened to simply "Charlie."
Likewise, the abbreviation "CIA" would be pronounced "Charlie-India-Alpha" in the NATO phonetic alphabet, which is probably where "Charlie's Indians" evolved from.
Jamiep: Spot on. I simply googled "Prodigy Charlie says", and it is clear that they have sampled the boy of this series, though at least at one place it is referred to as a series of TV-commercials. Anyway - this is definitely the right Charlie. Thanks.