I was actually joking around yesterday talking about making one, heh.
That's pretty cool though...I think it details it way too much though, makes it look kinda ugly. You should make it where it it's more random when it lays tiles, so like...maybe it only details 30% of the tiles or something like that.
Also, too bad you can't save the levels like that. The only way you can make it actually save is if you do it online with the serverside updateboard2.
Still though, it's nice.
[Edit] Oh, as far as saving goes...I totally didn't think about putting the script in a text file in the levels/npc's directory and doing it from there. [/Edit]