Seems like a perfect use case for EC2 on demand. Only run the VPN node when you are on an open wireless network and need the VPN security. Shut it down otherwise.
That would make it harder to run, but it would greatly reduce the cost. I'd pay $0.02 for an hour's worth of security while stopping off at a coffee shop.
It wouldn't be much harder to run. You can start and stop the instance using the command line tools, so you could easily wrap the whole lot into a script which started the server and brought up the VPN link, then when youre finished take down the link then the server, all in once command.
The API-based management is what makes cloud providers really special.
Your AWS dashboard would be compromised if you waited until you were on the open wireless network to run the EC2 instance, but attackers would not be able to compromise the EC2 instance. Once the instance has been created you can't change the Key Pair. You also can only download the private key associated with the Key Pair once, which is right when you create it. But of course, an attacker could stop or terminate your instance if he gained access to your AWS dashboard.
Not true: the dashboard runs entirely on SSL - which is still encrypted on an open wifi network. Compromising SSL isn't out of the question though, but highly unlikely.
That would make it harder to run, but it would greatly reduce the cost. I'd pay $0.02 for an hour's worth of security while stopping off at a coffee shop.