Most shared hosting can do 200 concurrent check made2own.com they can easily handle that kind of traffic for a forum they host some pretty large forum sites.
You would have to ask the sales department webhosting company before moving the accounts to them. You might see some webhosting companies offer 'space in the moon for $1', but I would never recommend to go with them, since they are simply overselling and your website will get shut down if it hog a bit of their server resources. I've PMed you regarding that, and will talk to you soon!
Hello djhassoo, We might be able to accommodate your forum. Take a look at the following thread. http://forums.digitalpoint.com/showthread.php?t=653676 If you're interested, drop me a PM and we'll see if we can work something out. Thanks.