I scored an 18V Danelectro zero hum wallwart from my local music store after a mix up with some patch I bought. They couldn't give me a refund (the difference between the two cables was $4) so I asked them what else they could offer, and they had this supply in a dusty corner.
Its a 180mA 18V supply, the DA-2. I happen to have some LM317s and I was wondering how to wire them up for 9V output. After reading the datasheet, I came up with this: