Call to the Lazyweb: PHP programming

I’m nearly finished with a rather radical overhaul of the Map of Human Sexuality, and one of the things I thought would be cool to do with it would be to make it interactive.

What I’d like to be able to do is to place it on a Web page, then allow folks to stick push pins in it by clicking or dragging on it. Ideally, folks could also, if they wanted, save it with a name/password, and be able to link to their version of it.

What I have: PHP, Perl (though I’d prefer PHP), mySQL. I know there must already be code floating around out there somewhere that does the heavy lifting (records mouse clicks, places a graphic of a pin over another graphic, saves the array of pin locations in a database), so it’s be pretty silly to code it all from scratch. Plus, y’know, I’m not sure my PHP chops are up to it.

But I’m not finding anything.

Anyone know of any open source code or libraries that might be useful?