Easyway to have email sent from my site automatically or ren

I have a site on hostingrails and have some Rails apps on there. I
just bought a cell phone that I can get yahoo email and .mobi web

How can set up a way that will automaticlly send email every 12 hours
to my account ? Do I need a cron job or is there an easier way ?

Can I set up .mobi pages from my site that I can see on my cell phone
without having to register a new site name ?