Write this off as another crazy idea of mine if you will, but I'm looking into the possibility of creating Application Appliances based around rapidly developed Ruby on Rails apps.

Consider the Google Search Appliance. Now imagine if instead of just a search engine appliance, you could have an appliance which offered GMail style web-mail and, perhaps, calendaring, and BaseCamp style features around an entire company?

The appliances could be heavily locked down Linux boxes running Postgres or MySQL set up to run a single app (or suite of apps) and accessable over the company network (or even VPN). A lot of companies want their applications in-house, as 37Signals have heard from some BaseCamp customers.. so this idea isn't too far fetched, and with the rapid development times offered by Ruby on Rails, you could even develop and fully customize applications on a per-customer basis, and then rent out the appliances on an annual basis.