This fare just won’t die… aaron1262 on Flyertalk reports that a mistake fare, where you go Italy (MXP or FCO) to Singapore, stay in Singapore, and go to the USA (SFO and EWR work so far) for ~$338 is back. There seems to be pretty wide availability, especially in December, April, and May. I haven’t played around with the fare too much yet.
You can book this on Orbitz. Use the multi-city function.