BellaOnline Forums Hobbies and Crafts Coin Collecting Inauguration Stamped Reagan bill??

I came across a wierd stamp on a bill and didn't know if it meant anything?

It has 1981 Inauguration Reagan something, it's in the other room, but it's a stamp thingy. Does it mean anything? Never seen anything like it. So, just curious, even why the stamp or how it got there to begin with.

Thanks