To elaborate on the story of the invention of the Post-it Note, Dr. Silver was looking for a bookmark that wouldn't fall out of his Hymn Book in Choir. (This is what reading every Newsweek special insert during childhood gets you) The adhesive he used for the Hymn bookmark had been tested and failed for a different product.

A few interesting Post It innovations: Post-it glue stick, which (much to my chagrin after assuming it was regular glue stick and using on a school project) affixes the object with the strength of a Post-it. I don't know why anyone would use it, nor if it is still manufactured (mine turned up in my pencil drawer and was labeled 'Not for individual sale').

Another, more recent Post-it product is the transparent post it. It's made of a sort of clear, thin, plastic. The best thing about these (besides the fact that they're more durable and you can see the text of whatever a normal, opaque Post-it would cover) is that when someone says "Wow, thats amazing. Clear adhesive!" you can say...

"Yeah. Like Scotch Tape."

(Take that.)