Yes, there is such an application that sends all inbound SMS to email.
I no longer have it installed but it was from Europe somewhere (parts of the header and such were in a different language). I'll do a search and see if I can find a link but I found out about it on this board, so I should be able to find it.
(I know the original poster wanted the entire conversation to go to email, but this just does inbound SMS, which will be fine for some users).
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