For a non-free project, I guess you will want to consider a non-free product:
Code Co-op (www.relisoft.com) does provide an email-based source control system for Windows (+ a Linux beta). An automatic 'dispatcher' tool emails the scripts out and processes them in.
It also lets you use your preferred tool to zip and encrypt the scripts before they are sent.
It worked for me on a project with remote developers, with only few technical quirks - but it's really easy to use. Licenses are up from USD 50 per developer, email support was good.
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For a non-free project, I guess you will want to consider a non-free product:
Code Co-op (www.relisoft.com) does provide an email-based source control system for Windows (+ a Linux beta). An automatic 'dispatcher' tool emails the scripts out and processes them in.
It also lets you use your preferred tool to zip and encrypt the scripts before they are sent.
It worked for me on a project with remote developers, with only few technical quirks - but it's really easy to use. Licenses are up from USD 50 per developer, email support was good.
NB: I have no financial interest in the tool.
hth -ivec