Ecommerce- product notification plugin

Hi all,

I’m trying to find a plugin which will allow customers to register for ‘product alerts’- i.e. they can register for tags and then when those tags are added to my store they receive a notification email.

Does anyone know of any plugin (or similar) for this? (I’ve spent ages trying to find one but can’t seem to find one anywhere!)

Any help/advice would be really helpful!

Thanks!