lucy24 - 2:11 am on Dec 3, 2011 (gmt 0)
Oops, just remembered. Been using this for years when pre-proofing ebooks. Same purpose, though the context is less sinister.
The exact content of the braces will depend on your editor's RegEx dialect, and possibly also the p/P toggle (meaning "is/isn't"). For those who don't speak RegEx, it simply means: find any adjacent occurrences of Latin and non-Latin script.