Just checking, on different lines though right ?
Chewing 200MB in 1 hour would require an avg speed of 56.888 KBps

= 455 kbps

> 384 kbps

lol, forgive me I couldn't resist...
That's not really correct - remember, both download
and upload are counted, and a 384 kbps line has a 128 kbps upload speed, giving you a total line speed of 512 kbps, and on that, it is entirely possible to do 200Mb in an hour, even on the 384 line. People seem to forget about the upload... It just makes the cap even more restrictive.

Also, downloading emails is all good and well, but you can add quite a bit on to that for forwarding the mails you do recieve.
On top of that, I'm a developer as well. I work on online apps. I spend the entire day in front of the pc. I would love to listen to streaming radio, but I can't afford to. I have to save a large chunk of my bandwidth for testing, research, and downloading development tools and components, as well as their updates. I'd love to download the beta version of Orcas to try it out (latest version of Microsoft's visual studio development environment, for those that don't know), but it is 4.5Gb on its own. I'll have to wait for it to turn up on a MSDN DVD.
There's also a lot of legal content available on things like bittorrent. So things using your upload will include things like bittorrent, skype (mostly use google talk's voice facilities myself), webcams and gaming. And if you're doing things like that, I've already managed to go through 4gb in a single day on my little 384k line...
Without doing anything illegal. 