After Gmail, its 30gigs now. They are offering 30GB of mail storage. But this one is not from a very big company & they have registered their site (30gigs.com) for only 2 years. The user interface may look good. If anyone is left with an invitation, send me that to mail@kiruthik.com 

Year back,  Hotmail gave 2MB & Yahoo  6MB, now there are offerings in GBs.

Update : I have many 30 Gigs invitations left to give out   Mail me, if you need it....