EDIT: It's Java, not Flash.

I've only played with this for a few minutes, but now I'm intrigued.

Along the bottom are the sampled artists, while the top has the samplers. You can either fish for artists and albums willy-nilly, or you can type in the artist's name in the field of the graph. Caps count, kids, so "Stevie Wonder" works while "stevie wonder" doesn't.

The search works backwards and forwards as well.

Here's your link: http://jessekriss.com/projects/samplinghistory/