All shared packages come with unlimited POP3/IMAP mailboxes. You will have an SMTP server too. SSH is available but requires identification faxing/emailing over to us so we can activate.
We've been here for 9 years already, so hopefully we should be around for at least another 9! ;)
We've got Ruby already installed and we offer Ruby on Rails so Sinatra should be okay to install. Obviously on the shared platform anything considered highly intensive or anything which will require ports opening won't be allowed. You'll need a VPS for that.
We do a full 30-day money back guarantee on all shared web hosting packages if something doesn't suit your needs.
Oh sorry, yes, for SSH access. We'd need a photographic ID scan (driving licence or passport) plus a scan of a recent utility bill for SSH activation on shared hosting accounts. That isn't required for VPSes or dedicated servers.