I've always made use of what I'd probably class as a 'bug', and assigned to zero, e.g.:
0 = execVM "myscript.sqf"
It doesn't error, it doesn't change the value of zero, and it simply... works. There's no danger of redefining another variable or reserved keyword, and even to someone reading the code (who is unfamiliar with SQF) it becomes relatively obvious, relatively quickly, that it's just used for discarding the handle.
Normally, in a language, I'd expect this to error or, maybe (but I'd cringe), to allow zero to be re-assigned to the new value (have fun with maths, after evaluating 0=1, kids) - but the way BIS have allowed this has given me a useful way to 'throw away' script handles