I have read that one can use the T-mobile prepaid SIMs to get web/email connectivity.(I think) I was going to use it instead of paying for a Blackberry plan, (I'd only use the connectivity at work for a boredom fighter) I would like to use Yahoo messenger, et al, and maybe some email. So would that work, and how do I get a hold of a T-mobile prepaid SIM? There are no local offices in my area.