My wife tried to download a ringtone to her Nokia 3000 series from the ATT Wireless website. The download failed, though I don't know if it failed during the download or when she tried to load the ringtone into her phone.
After that attempted download, the battery on her phone began to discharge in a matter of hours instead over over a few days as it had before then. She hadn't used the phone at all and it still discharged.
Thinking something was wrong with her battery, I took both of our phones to the local Cingular store to either get hers fixed or to upgrade. I upgraded both phones to Motorola V220s. The salesman used new SIM cards in the Motorolas instead of using the SIM cards in the Nokias.
When I got home, I put her Nokia on the charger to keep the battery going until I could pull the phone numbers off of it for her new phone. We charged up both of the new Motorolas at the same time.
The next evening, I pulled her new Motorola and her old Nokia off the chargers. I entered her phone numbers for her into the Motorola and set the Nokia aside. Less than a day later, her Motorola is chirping because her battery is dying. I put it back on the charger and notice that her old Nokia, the one that had been discharging the battery in a matter of hours, still had a full charge.
My new Motorola is keeping it's charge just fine.
Is there something about a ringtone download that would cause some sort of drain on a battery if it isn't completed? I don't see any indication of new messages or any communication with the ATT site that the download is trying to complete itself, or anything from her phone showing that it is sending some sort of signal to confirm the download. I don't know enough about where to check, though.
So, in a nutshell
1. Wife tries to download ringtone, but it never completes.
2. Nokia loses charge rapidly after having held charge for days at a time before the download attempt
3. Get new Motorola with new SIM card but the same phone number.
4. Motorola battery discharges rapidly, old Nokia battery now holds charge for several days.
Any ideas? I am going to change out my sim card with hers when I get home this evening to see if it is in fact her battery or something tied in to her phone number.

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic