Trotify

Better than ringing a stupid bell and yelling “Outta my way, butthead,” Trotify dignifies the alert.  Downloadable plans are available for free here; 3D printable files ($4.57) here.

[Found here a few years back.]

Kitchen Knife Potato 7

This image is from a book on radio sound effects. It demonstrates how to easily replicate the sound of a kitchen knife slicing into a potato.

[Found here.]