'MailGrin', this sounds like an email client to me, like Thunderbird for example. The Grin conjures up thoughts of no spam and viral nasties breaking through the Mail Clients super tight backend.
I like the name and I think it would make a fantastic name for an Email Client. Can you code? If so I would work on the concept for a few hours per week.
Undeveloped, as is $500 to $2000
Regards.matt