Alitalia is offering 2,000 bonus miles just for registering with their program by March 30, 2013. They’re offering a further 2,000 bonus miles if you have any activity with them within three months, including a Membership Rewards points transfer. Then you can get another 2,000 miles by flying with them by April 30, 2013.
Alitalia’s program can be extremely lucrative for SkyTeam redemptions, so you might as well sign up, especially if you have Membership Rewards points you might be able to combine with this balance.
(Tip of the hat to Tiffany)