Alanis Morrisette couldn't have possibly thought up something this ironic to put in her hit song. On the same day Sprint launches an ad campaign trashing T-Mobile's "unlimited" plan for throttling its data speeds, the Now Network announced that it intends to begin throttling Virgin Mobile's broadband sometime in October. Those who use larger amounts of data on the prepaid brand will experience the briskness of 256kbps as soon as they hit a monthly threshold of 2.5GB. This won't affect postpaid customers on Sprint for the time being, but it's hitting a little too close to home. After all,