The noise gate is capable of a variety of envelope shaping effects, and is a highly creative tool as well as a problem solver.
One classic trick is to put a more-or-less continuous signal through the gate, such as heavily distorted chords from an electric guitar, and then use the noise gate's external key to chop it up into a rhythm. Like this:
You can't get the same sound in any other way and it is well worth trying out and adding to your repertory of techniques.
Drum envelope shaping
Another useful gate effect is to compress the sound of an individual drum, then gate it.
This works particularly well on drum samples which have a little bit of reverb on them.
A compressor can shape the envelope of the sound by emphasizing the attack (by setting a slow attack time on the compressor, allowing the initial transient to get through unaltered), or by allowing the reverb to increase in level as the drum dies away.
The noise gate can then further process the envelope using the attack, hold and release controls.
First popularized in the 1980s, gated reverb has become something of a cliche. But as a technique, it is still well worth knowing about. It goes like this:
You now have Phil Collins-style gated reverb! You could use a distant mic as the reverb source, as an alternative to the reverb unit.
If you're not using the external trigger input of your noise gate, you're missing out on so many interesting sounds that you can't get in any other way.