Indeed, zzattack was the first one I saw doing this. It's good to mention it. There are two important things to note:
1) It only works in the case of an alias, not usable in an event or from the command line.
2) For someone reading code, it is a lot more straightforward to have a uniform identifier such as $null() or $noop().
Other than that I agree, it's quite handy, although maybe this is just us again relying on a quirk such as the $(,,<input>) thing that we unfortunately can no longer use since version 6.17.
