diff --git a/similar.pike b/similar.pike
new file mode 100644
index 00000000..e3924bd7
--- /dev/null
+++ b/similar.pike
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+//Find the most similar pair of a set of files
+//All arguments that can be statted are files; all others are passed on to diff(1).
+//All pairs of files are tested exhaustively (though only 'forwards' - the same files
+//in the other order won't be tested), and whichever pair results in the least bytes
+//of diff output is printed to stdout.
+int main(int argc,array(string) argv)
+{
+	array(string) files=filter(argv[1..],file_stat);
+	array(string) args=argv[1..]-files;
+	string bestoutput;
+	foreach (files;int i;string fn1) foreach (files[i+1..],string fn2)
+	{
+		string output=Process.run(({"diff"})+args+({fn1,fn2}))->stdout;
+		if (!bestoutput || sizeof(bestoutput)>sizeof(output)) bestoutput=output;
+	}
+	write(bestoutput);
+}