One thing not being addressed though is the key of this question: Is there a way to set it up so that only some accounts are checked based on connection.

Let me present it another way. I have a huge work e-mail box, and a large spam-laden personal mail box that take ages to update and lots of band width to do so. I also have a spam-blocked e-mail or two that only a few people have. I always want modest to check the low flow accounts, but NEVER want it to check the large ones unless I'm on my home or work network, respectively.

Everything presented so far is still about an "all or nothing" approach, enabling all accounts for update or not based on connection. That's good for some people, but I was hoping for a "some or more" approach.

Currently the only way I know how to do this is to setup per-connection smtp/pop/imap connection settings. You put bogus credentials in the main one, and proper credentials in the connections you want to use that account with. But that takes a lot of work, and causes errors every check when not on the high-use networks.

I wish there were just an "enable/disable" option, like HAM has for repositories, per e-mail account. Enabling and disabling those by hand, or with gconf based on connection could then be much simpler.