WiFi directly to smartphone - thoughts please

I've been thinking about something, but need some 2nd (perhaps & 3rd (and higher order)) opinions....

What are the technical problems w/ going directly from a WiFi network directly to my smartphone, with, for example, an email - without having to go through the internet.

I've got a feeling there are some pretty daunting technical considerations, but - if so, what are they?

PlumBob

Well, it's the PDAnet thread below that got me off on this, actually. Pdanet , of course, still relies on 3/4G connectivity to push either an email or sms text into the cell network and then whatever happens to it happens - either through the cell service or internet. I'm thinking more basic than that - directly from computer to phone using only the computer's wifi capability and the phone's ability to connect to a wireless network. Text message via VHF ham radio if you will - but using the computer and phone.

I imagine the phone makers have designed this kind of operability away, so I may have already run aground.