We have a couple of smartphones here we use when traveling, just so we can stay in touch with our inboxes. We have used T-Mobiles T-Zones service for this which is $5.99 a month as it allows for POP3 mail access.
We recently upgraded to some BlackBerrys and found out that you cannot get email on them with T-Zones, you have to pay for their $20.00 monthly BlackBerry service. We were just going to switch to another model smartphone that allowed POP3 access through T-Zones because the extra expense was not worth it to us, then we figured out how to use POP3 on the BlackBerrys. This is not a hack or anything like that, nor does it allow for push email like the regular BlackBerry service.
Basically all you need to do is (assuming you already have T-Zones) open a browser and click the scroll button and select Go To. Then input this link:
http://logicmail.sourceforge.net/ota/
This will allow you to download the LogicMail POP3 and IMAP client for BlackBerry. Once the install is complete, the LogicMail icon will appear in the Applications folder of your BlackBerry. Again, this does not allow for regular push email (won't notify you of new incoming messages), it is just a mail client where you can view your inbox and send/receive mail. But this is exactly what we want to be able to do- just check our inboxes from the road. Mission accomplished!
***note: this was done on some BlackBerry 7105t phones but should work on other BlackBerry models we assume***