Just a little bit of househeeping:
Effective now, or rather about a week ago, STi activations get new, slightly better plans. They're still annoying to me, but they are better. The 10 cent per day plan is now 10 cents flat per minute, instead of 10\12. And the 7.9 cent per minute plan is now 25, instead of 39, center per day. Also, the "you have $xx.xx and xx minutes" reminder at the beginning of each call is gone (yay). You can listen to it by dialing *555 from your STi phone.
Also, PosaTec.com has $50 T-Mobile refills for $44.99. Nice as it is, especially when you remember that, by calling T-Mobile To Go customer service, you can "stack" two $50 refills into one $100 refill. Which gets you a $100 refill for $89.98...a cool 10%\$10 off. Granted, CheapPhoneCards has the same card, without the whole stacking bit, for $92.22 or so, and you get $2.63 or so in reward points for the purchase, but if you want your airtime for less outright you can use PosaTec.
Hmmm...interesting how I'm selling both an STi Mobile phone and a T-Mobile To Go SIM card right now... :)