any suggestions? cheap air or train or bus???
According to whichbudget.com, there are no budget airlines that fly the Nice-Milan route.
The Eurolines site is down right now so I couldn't determine if there is bus service.
Even so, I'm sure the best choice is to take the train. The standard 2nd class fare is around 30 EUR. Smart Price fares, when available and booked well in advance (up to 90 days) at sncf.com, are as low as 15 EUR.
I'd say train too. Fast and easy. By the time you get to the airport, go through security, wait for boarding, get on the plane, take off on time assuming it does this etc etc you probably could have been there already on the train.