My usage was more than 150% again as much in the first month we had the Mifi than before when we had a 3G FiveSpot. And we still had the 3G hotspot for the first 8 days of that month. Granted, with my child home from college we asked to add a four more GBs but- 10GB to 26 + GB? Because of the mid billing change of plan, I could not track usage online but I called 2 days before the billing period ended and was told I still had 4 GB. Bercause of that phone call eror, that last overage (4GB) was corrected on the bill after I called Verizon Customer Service. I am awaiting a bill audit but I checked hourly usage for the last two days and, at night, while we were asleep, and our computers were off or asleep, we show data usage in approx. 15 minute increments all night. 4.6 MB total between 1AM and 7AM. (And no- no one should have been able to sit near by and pirate our signal- we live in the middle of a vast field of corn stubble). This has gone on every night as far back as I checked. And each overage varies-though most hover around 135-145 KBs. We are going to try some closer tracking for the next while but this seems like a device problem and there are other posts that suggest there is one. (I will post the outcome of this issue after the billing audit and, I feel sure, more long discussions with Verizon.) Late reporting from non-Verizon towers doesn't seem a logical answer to these constant and regular data usages. Any one else tracked the details of their overages and found similar patterns?