We're switching instant messenger programs here, and the new one has a very penetrating sound for message alert- and when my neighbor receives a message, it sounds like it's coming from my laptop...

So I was going to customize my alert sounds- looking for something not too obnoxious- like a slide rack or release on a pistol, maybe a bolt release on an AR.. I found a AK47 rack, but it's a bit long to hear every time someone sends an IM

any suggestions on where to find short, functional sounds that will be unique?